Reinforced poly(phenylene ether)-polysiloxane block copolymer composition, and article comprising same

ABSTRACT

A reinforced poly(phenylene ether)-polysiloxane block copolymer composition includes specific amounts of a poly(phenylene ether)-polysiloxane block copolymer reaction product, a flame retardant, and a reinforcing filler. The composition exhibits a desirable balance of flame retardancy, heat resistance, and stiffness relative to a corresponding poly(phenylene ether) composition, and it is useful to fabricate articles including fuser holders for electrophotographic copiers.

BACKGROUND OF THE INVENTION

Poly(phenylene ether) is a type of plastic known for its excellent waterresistance, dimensional stability, and inherent flame retardancy.Properties such as strength, stiffness, chemical resistance, and heatresistance can be tailored by blending it with various other plastics inorder to meet the requirements of a wide variety of consumer andindustrial products, for example, plumbing fixtures, electrical boxes,automotive parts, and insulation for wire and cable.

Some applications for poly(phenylene ether)-based compositions requiresignificant flame retardant capability. Examples include molded articlesin the construction, transportation, electronics, and solar powerindustries. Poly(phenylene ether) is inherently flame retardant, but itis often blended with other components, such as impact modifiers andflow promoters, that reduce the flame retardancy of the resultingcomposition even as they improve its processing and mechanicalproperties. So, flame retardant additives are often required for blendsof poly(phenylene ether)s with these other components.

Some molded articles require a flammability rating of V-0 in the 20millimeter Vertical Burning Flame Test of Underwriter's LaboratoryBulletin 94 “Tests for Flammability of Plastic Materials, UL 94”. ThisV-0 rating can be difficult to achieve in a poly(phenylene ether)composition, even when flame retardant concentration is increased, andconcentrations of flammable components are decreased. And when the V-0rating is achievable, it often comes at the expense of diminished heatresistance and stiffness.

There remains a need for a poly(phenylene ether)-containing moldingcomposition that exhibits a UL 94 V-0 rating while maintaining high heatresistance and stiffness.

BRIEF SUMMARY OF EMBODIMENTS OF THE INVENTION

One embodiment is a composition, comprising: 0.5 to 91 weight percent ofa poly(phenylene ether)-polysiloxane block copolymer reaction productcomprising a first poly(phenylene ether) and a poly(phenyleneether)-polysiloxane block copolymer; 4 to 25 weight percent of a flameretardant comprising an organophosphate ester, a phosphazene, or acombination thereof; and 5 to 40 weight percent of a reinforcing filler;wherein all weight percents are based on the total weight of thecomposition.

Another embodiment is a composition, comprising: 0.5 to 5 weight percentof a poly(phenylene ether)-polysiloxane block copolymer reaction productcomprising a first poly(phenylene ether) and a poly(phenyleneether)-polysiloxane block copolymer; wherein the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; 50 to 70 weight percent of a secondpoly(phenylene ether) comprising a homopolymer of 2,6-dimethylphenol; 6to 14 weight percent of a flame retardant comprising an organophosphateester; 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; and15 to 25 weight percent of glass fibers; wherein the compositioncomprises less than or equal to 1 weight percent of each of polyamidesand polyesters; and wherein all weight percents are based on the totalweight of the composition.

Another embodiment is an article comprising a composition, comprising:0.5 to 91 weight percent of a poly(phenylene ether)-polysiloxane blockcopolymer reaction product comprising a first poly(phenylene ether) anda poly(phenylene ether)-polysiloxane block copolymer; 4 to 25 weightpercent of a flame retardant comprising an organophosphate ester, aphosphazene, or a combination thereof; and 5 to 40 weight percent of areinforcing filler; wherein all weight percents are based on the totalweight of the composition.

These and other embodiments are described in detail below.

DETAILED DESCRIPTION OF THE INVENTION

The present inventors have determined that the difficult-to-achieveproperty combination of a UL 94 V-0 rating, high heat resistance, andhigh stiffness is provided by a composition comprising 0.5 to 91 weightpercent of a poly(phenylene ether)-polysiloxane block copolymer reactionproduct comprising a first poly(phenylene ether) and a poly(phenyleneether)-polysiloxane block copolymer; 4 to 25 weight percent of a flameretardant comprising an organophosphate ester, a phosphazene, or acombination thereof; and 5 to 40 weight percent of a reinforcing filler;wherein all weight percents are based on the total weight of thecomposition. Specifically, the composition can exhibit a flammabilityrating of V-0 at a sample thickness less than or equal to 1.5millimeters in the 20 millimeter Vertical Burning Flame Test ofUnderwriter's Laboratory Bulletin 94 “Tests for Flammability of PlasticMaterials, UL 94”, a heat deflection temperature of at least 110° C.determined according to ASTM D 648-07 using a stress of 1.82 megapascals(MPa) and a sample thickness of 6.4 millimeters, a flexural modulus ofat least 3,500 megapascals measured at 23° C. according to ASTM D790-07e1 using a sample thickness of 6.4 millimeters. As demonstrated inthe working examples below, in some embodiments the V-0 rating can beachieved at a thickness at least as low as 0.75 millimeters, the heatdeflection temperature can be at least as high as 168° C., and theflexural modulus can be at least as high as 6,178 megapascals. In someembodiments, the composition exhibits the property combination of a UL94 V-0 rating at a thickness of 1.5 millimeters, a heat deflectiontemperature of at least 150° C. determined according to ASTM D 648-07using a stress of 1.82 megapascals (MPa) and a sample thickness of 6.4millimeters, and a flexural modulus of at least 5,000 megapascalsmeasured at 23° C. according to ASTM D 790-07e1 using a sample thicknessof 6.4 millimeters

In addition to being superior to compositions based on poly(phenyleneether) homopolymers, the present composition is superior to alternativematerials used in applications requiring a UL 94 V-0 rating. Forexample, alternative glass-filled poly(ethylene terephthalate)compositions and glass-filled poly(butylene terephthalate) compositionsoften utilize halogenated flame retardants to achieve a V-0 rating,whereas the present composition does not require a halogenated flameretardant. The glass-filled polyester compositions, which are based oncrystalline resins, also exhibit greater warpage (part distortion) thanthe present composition utilizing amorphous resin.

The composition comprises a poly(phenylene ether)-polysiloxane blockcopolymer reaction product which in turn comprises a poly(phenyleneether)-polysiloxane block copolymer and a poly(phenylene ether) (withoutan incorporated polysiloxane block). For brevity, the poly(phenyleneether)-polysiloxane block copolymer reaction product is sometimesreferred to herein as the “reaction product”. The poly(phenyleneether)-polysiloxane block copolymer reaction product is synthesized byoxidative polymerization of a mixture of monohydric phenol andhydroxyaryl-terminated polysiloxane. This oxidative polymerizationproduces poly(phenylene ether)-polysiloxane block copolymer as thedesired product and poly(phenylene ether) as a by-product. Thispoly(phenylene ether) present in the reaction product is sometimesreferred to herein as the “first poly(phenylene ether)” to distinguishit from a “second poly(phenylene ether)” that is optionally present inthe composition and not derived from the poly(phenyleneether)-polysiloxane block copolymer reaction product. It is difficultand unnecessary to separate the first poly(phenylene ether) from thepoly(phenylene ether)-polysiloxane block copolymer. The poly(phenyleneether)-polysiloxane block copolymer can therefore be incorporated intothe present composition as a “poly(phenylene ether)-polysiloxane blockcopolymer reaction product” that comprises both the first poly(phenyleneether) and the poly(phenylene ether)-polysiloxane block copolymer.

The poly(phenylene ether)-polysiloxane block copolymer comprises apoly(phenylene ether) block and a polysiloxane block. The poly(phenyleneether) block is a residue of the polymerization of the monohydricphenol. In some embodiments, the poly(phenylene ether) block comprisesphenylene ether repeating units having the structure

wherein for each repeating unit, each Z¹ is independently unsubstitutedor substituted C₁-C₁₂ hydrocarbyl provided that the hydrocarbyl group isnot tertiary hydrocarbyl, C₁-C₁₂ hydrocarbylthio, or C₁-C₁₂hydrocarbyloxy; and each Z² is independently hydrogen, unsubstituted orsubstituted C₁-C₁₂ hydrocarbyl provided that the hydrocarbyl group isnot tertiary hydrocarbyl, C₁-C₁₂ hydrocarbylthio, or C₁-C₁₂hydrocarbyloxy. In some embodiments, the poly(phenylene ether) blockcomprises 2,6-dimethyl-1,4-phenylene ether repeating units, that is,repeating units having the structure

2,3,6-trimethyl-1,4-phenylene ether repeating units, or a combinationthereof.

The polysiloxane block is a residue of the hydroxyaryl-terminatedpolysiloxane. In some embodiments, the polysiloxane block comprisesrepeating units having the structure

wherein each occurrence of R¹ and R² is independently hydrogen or C₁-C₁₂hydrocarbyl; and the polysiloxane block further comprises a terminalunit having the structure

wherein Y is hydrogen, C₁-C₁₂ hydrocarbyl, or C₁-C₁₂ hydrocarbyloxy, andwherein each occurrence of R³ and R⁴ is independently hydrogen or C₁-C₁₂hydrocarbyl. In some embodiments, the polysiloxane repeating unitscomprise dimethylsiloxane (—Si(CH₃)₂O—) units. In some embodiments, thepolysiloxane block has the structure

wherein n is, on average, 20 to 60.

In a very specific embodiment, the poly(phenylene ether)-polysiloxaneblock copolymer comprises a poly(phenylene ether) block comprisingphenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60.

The hydroxyaryl-terminated polysiloxane comprises at least onehydroxyaryl terminal group. In some embodiments, thehydroxyaryl-terminated polysiloxane has a single hydroxyaryl terminalgroup, in which case a poly(phenylene ether)-polysiloxane diblockcopolymer is formed. In other embodiments, the hydroxyaryl-terminatedpolysiloxane has two hydroxyaryl terminal groups, in which case in whichcase poly(phenylene ether)-polysiloxane diblock copolymer and/orpoly(phenylene ether)-polysiloxane-poly(phenylene ether) triblockcopolymer are formed. It is also possible for the hydroxyaryl-terminatedpolysiloxane to have a branched structure that allows three or morehydroxyaryl terminal groups and the formation of corresponding branchedblock copolymers.

In some embodiments, the hydroxyaryl-terminated polysiloxane comprises,on average, 20 to 80 siloxane repeating units, specifically 25 to 70siloxane repeating units, more specifically 30 to 60 siloxane repeatingunits, still more specifically 35 to 50 siloxane repeating units, yetmore specifically 40 to 50 siloxane repeating units. The number ofsiloxane repeating units in the polysiloxane block is essentiallyunaffected by the copolymerization and isolation conditions, and it istherefore equivalent to the number of siloxane repeating units in thehydroxyaryl-terminated polysiloxane starting material. When nototherwise known, the average number of siloxane repeating units perhydroxyaryl-terminated polysiloxane molecule can be determined bynuclear magnetic resonance (NMR) methods that compare the intensities ofsignals associated with the siloxane repeating units to those associatedwith the hydroxyaryl terminal groups. For example, when thehydroxyaryl-terminated polysiloxane is a eugenol-cappedpolydimethylsiloxane, it is possible to determine the average number ofsiloxane repeating units by a proton nuclear magnetic resonance (¹H NMR)method in which integrals for the protons of the dimethylsiloxaneresonance and the protons of the eugenol methoxy group are compared.

In some embodiments, the poly(phenylene ether)-polysiloxane blockcopolymer reaction product has a weight average molecular weight of atleast 30,000 atomic mass units. For example, the reaction product canhave a weight average molecular weight of 30,000 to 150,000 atomic massunits, specifically 35,000 to 120,000 atomic mass units, morespecifically 40,000 to 90,000 atomic mass units, even more specifically45,000 to 70,000 atomic mass units. In some embodiments, thepoly(phenylene ether)-polysiloxane block copolymer reaction product hasa number average molecular weight of 10,000 to 50,000 atomic mass units,specifically 10,000 to 30,000 atomic mass units, more specifically14,000 to 24,000 atomic mass units.

In some embodiments, the poly(phenylene ether)-polysiloxane blockcopolymer reaction product has an intrinsic viscosity of at least 0.3deciliter per gram, as measured by Ubbelohde viscometer at 25° C. inchloroform. In some embodiments, the intrinsic viscosity is 0.3 to 0.5deciliter per gram, specifically 0.31 to 0.5 deciliter per gram, morespecifically 0.35 to 0.47 deciliter per gram.

One indication of the efficiency with which the hydroxyaryl-terminatedpolysiloxane is incorporated into block copolymer is the lowconcentration of so-called poly(phenylene ether) “tail” groups in thereaction product. In a homopolymerization of 2,6-dimethylphenol, a largefraction of product molecules have a so-called head-to-tail structure inwhich the linear product molecule is terminated on one end by a3,5-dimethyl-4-hydroxyphenyl “head” and on the other end by a2,6-dimethylphenoxy “tail”. Thus, when the monohydric phenol consists of2,6-dimethylphenol, the poly(phenylene ether) tail group has thestructure

wherein the 3-, 4-, and 5-positions of the ring are substituted withhydrogen atoms (that is, the term “2,6-dimethylphenoxy” refers to amonovalent group and does not encompass divalent2,6-dimethyl-1,4-phenylene ether groups). In a copolymerization ofmonohydric phenol with hydroxyaryl-terminated polysiloxane,incorporation of the hydroxyaryl-terminated polysiloxane into blockcopolymer will reduce the concentration of phenylene ether “tail”groups. Thus, in some embodiments, the monohydric phenol consists of2,6-dimethylphenol, and the reaction product of comprises less than orequal to 0.4 weight percent, specifically 0.1 to 0.4 weight percent, of2,6-dimethylphenoxy groups, based on the weight of the reaction product.The 2,6-dimethylphenoxy tail end groups are characteristic ofpoly(2,6-dimethyl-1,4-phenylene ether) homopolymer with a head-to-tail(hydroxy-monoterminated) structure in which the linear product moleculeis terminated on one end by a 3,5-dimethyl-4-hydroxyphenyl “head” and onthe other end by a 2,6-dimethylphenoxy “tail”. So, the low concentrationof 2,6-dimethylphenoxy tail end groups is an indication that thereaction product comprises a reduced concentration of suchmonofunctional homopolymer and an increased concentration of the desiredpoly(phenylene ether)-polysiloxane block copolymer.

The poly(phenylene ether)-polysiloxane block copolymer reaction productcan further include groups derived from a diphenoquinone, which isitself an oxidation product of the monohydric phenol. For example, whenthe monohydric phenol is 2,6-dimethylphenol, the diphenoquinone is3,3′,5,5′-tetramethyl-4,4′-diphenoquinone. During the build phase of thecopolymerization, the diphenoquinone is typically incorporated into the“tail” end of a head-to-tail poly(phenylene ether) as the correspondingbiphenyl group. Through further reactions, the terminal biphenyl groupcan become an internal biphenyl group in the first poly(phenylene ether)chain. In some embodiments, the monohydric phenol consists of2,6-dimethylphenol, and the reaction product comprises 0.1 to 2.0 weightpercent, and specifically 1.1 to 2.0 weight percent, of2,6-dimethyl-4-(3,5-dimethyl-4-hydroxyphenyl)-phenoxy (“biphenyl”)groups. The biphenyl groups are present only in bifunctional(head-to-head or hydroxyl-diterminated) structure. So, the lowconcentration of biphenyl group is an indication that the reactionproduct comprises a reduced concentration of such bifunctionalhomopolymer and an increased concentration of the desired poly(phenyleneether)-polysiloxane block copolymer.

The oxidative copolymerization can be conducted with a reaction timegreater than or equal to 110 minutes. The reaction time is the elapsedtime between initiation and termination of oxygen flow. (Although, forbrevity, the description herein repeatedly refers to “oxygen” or “oxygenflow”, it will be understood that any oxygen-containing gas, includingair, can be used as the oxygen source.) In some embodiments, thereaction time is 110 to 300 minutes, specifically 140 to 250 minutes,more specifically 170 to 220 minutes.

The oxidative copolymerization can include a “build time”, which is thetime between completion of monomer addition and termination of oxygenflow. In some embodiments, the reaction time comprises a build time of80 to 160 minutes. In some embodiments, the reaction temperature duringat least part of the build time can be 40 to 60° C., specifically 45 to55° C.

The poly(phenylene ether)-polysiloxane block copolymer reaction productcan be isolated from solution by an isolation procedure that minimizesvolatile and nonvolatile contaminants. For example, in some embodimentsthe reaction product comprises less than or equal to 1 weight percent oftotal volatiles, specifically 0.2 to 1 weight percent of totalvolatiles. In some embodiments the monomer mixture is oxidativelycopolymerized in the presence of a catalyst comprising a metal (such ascopper or manganese), and the poly(phenylene ether)-polysiloxane blockcopolymer reaction product comprises less than or equal to 100 parts permillion by weight of the metal, specifically 5 to 100 parts per millionby weight of the metal, more specifically 10 to 50 parts per million byweight of the metal, even more specifically 20 to 50 parts by weight ofthe metal, based on the weight of the poly(phenylene ether)-polysiloxaneblock copolymer reaction product.

Certain isolation procedures make it possible to assure that thepoly(phenylene ether)-polysiloxane block copolymer reaction product isessentially free of residual hydroxyaryl-terminated polysiloxanestarting material. In other words, these isolation procedures assurethat the polysiloxane content of the reaction product consistsessentially of the polysiloxane blocks of poly(phenyleneether)-polysiloxane block copolymer. After termination of thecopolymerization reaction, the poly(phenylene ether)-polysiloxane blockcopolymer reaction product can be isolated from solution using methodsknown in the art for isolating poly(phenylene ether)s from solution. Forexample, the poly(phenylene ether)-polysiloxane block copolymer reactionproduct can be isolated by precipitation with an antisolvent comprisingat least 50 weight percent of one or more C₁-C₆ alkanols, such asmethanol, ethanol, n-propanol, or isopropanol. The use of anisopropanol-containing antisolvent is advantageous because isopropanolis a good solvent for unreacted hydroxyaryl-terminated polysiloxane.Therefore, precipitation and/or washing with an isopropanol-containingantisolvent (e.g., isopropanol alone) substantially removehydroxyaryl-terminated polysiloxane from the isolated product.

Using these methods, it is possible to produce a poly(phenyleneether)-polysiloxane block copolymer reaction product comprising lessthan or equal to 1.5 weight percent of the hydroxyaryl-terminatedpolysiloxane, specifically less than or equal to 1 weight percent of thehydroxyaryl-terminated polysiloxane, more specifically less than orequal to 0.5 weight percent of the hydroxyaryl-terminated polysiloxane,still more specifically less than or equal to 0.1 weight percent of thehydroxyaryl-terminated polysiloxane, based on the total weight of thepoly(phenylene ether)-polysiloxane block copolymer reaction product.

The composition comprises less than or equal to 10 parts by weight ofhydroxyaryl-terminated polysiloxane not covalently bound in thepoly(phenylene ether)-polysiloxane block copolymer for each 100 parts byweight of hydroxyaryl-terminated polysiloxane covalently bound in thepoly(phenylene ether)-polysiloxane block copolymer. Within this limit,the amount of hydroxyaryl-terminated polysiloxane not covalently boundin the poly(phenylene ether)-polysiloxane block copolymer can be lessthan or equal to 5 parts by weight, specifically less than or equal to 3parts by weight, more specifically less than or equal to 2 parts byweight, even more specifically less than or equal to 1 part by weight.In some embodiments, the composition comprises less than or equal to 0.1weight percent of polysiloxane not covalently bound in thepoly(phenylene ether)-polysiloxane block copolymer.

In some embodiments, the poly(phenylene ether)-polysiloxane blockcopolymer reaction product incorporates greater than 75 weight percent,of the hydroxyaryl-terminated polysiloxane starting material into thepoly(phenylene ether)-polysiloxane block copolymer. Specifically, theamount of the hydroxyaryl-terminated polysiloxane incorporated into thepoly(phenylene ether)-polysiloxane block copolymer can be at least 80weight percent, more specifically at least 85 weight percent, still morespecifically at least 90 weight percent, yet more specifically at least95 weight percent.

Additional details relating to the preparation, characterization, andproperties of the poly(phenylene ether)-polysiloxane block copolymerreaction product can be found in U.S. Pat. No. 8,017,697 to Carrillo etal., and in copending U.S. patent application Ser. No. 13/169,137 ofCarrillo et al., filed Jun. 27, 2011.

In some embodiments, the composition comprises 0.025 to 5 weight percentof polysiloxane covalently bound in the poly(phenyleneether)-polysiloxane block copolymer. In other words, the poly(phenyleneether)-polysiloxane block copolymer contributes 0.025 to 5 weightpercent of polysiloxane to the composition as a whole. In someembodiments, the covalently bound polysiloxane amount is 0.025 to 1weight percent, specifically 0.025 to 0.5 weight percent, based on thetotal weight of the composition. In some embodiments, such as, forexample, when the poly(phenylene ether)-polysiloxane block copolymerreaction product is purified via precipitation in isopropanol, thepolysiloxane content of the composition consists essentially ofpolysiloxane that has been incorporated into the poly(phenyleneether)-polysiloxane block copolymer. In some embodiments, the reactionproduct comprises 1 to 8 weight percent siloxane repeating units and 12to 99 weight percent phenylene ether repeating units, based on the totalweight of the reaction product. Within these ranges, the amount ofsiloxane repeating units can be 2 to 7 weight percent, specifically 3 to6 weight percent, more specifically 4 to 5 weight percent; and theamount of phenylene ether repeating units can be 93 to 98 weightpercent, specifically 94 to 97 weight percent, more specifically 95 to96 weight percent. The reaction product can include relatively smallamounts of very low molecular weight species. Thus, in some embodiments,the reaction product comprises less than 25 weight percent of moleculeshaving a molecular weight less than 10,000 atomic mass units,specifically 5 to 25 weight percent of molecules having a molecularweight less than 10,000 atomic mass units, more specifically 7 to 21weight percent of molecules having a molecular weight less than 10,000atomic mass units. In some embodiments, the molecules having a molecularweight less than 10,000 atomic mass units comprise, on average, 5 to 10weight percent siloxane repeating units, specifically 6 to 9 weightpercent siloxane repeating units.

Similarly, the reaction product can also include relatively smallamounts of very high molecular weight species. Thus, in someembodiments, the reaction product comprises less than 25 weight percentof molecules having a molecular weight greater than 100,000 atomic massunits, specifically 5 to 25 weight percent of molecules having amolecular weight greater than 100,000 atomic mass units, morespecifically 7 to 23 weight percent of molecules having a molecularweight greater than 100,000 atomic mass units. In some embodiments, themolecules having a molecular weight greater than 100,000 atomic massunits comprise, on average, 3 to 6 weight percent siloxane repeatingunits, specifically 4 to 5 weight percent siloxane repeating units.

In a very specific procedure for preparing the poly(phenyleneether)-polysiloxane block copolymer reaction product, the monohydricphenol is 2,6-dimethylphenol; the hydroxyaryl-terminated polysiloxane isa eugenol-capped polydimethylsiloxane comprising 35 to 60dimethylsiloxane units; the oxidative copolymerization is conducted witha reaction time of 170 to 220 minutes; and the hydroxyaryl-terminatedpolysiloxane constitutes 2 to 7 weight percent of the combined weight ofthe monohydric phenol and the hydroxyaryl-terminated polysiloxane.

The composition comprises 0.5 to 91 weight percent of the poly(phenyleneether)-polysiloxane block copolymer reaction product, based on the totalweight of the composition. In some embodiments, the reaction productamount is 30 to 91 weight percent, specifically 55 to 85 weight percent,more specifically 60 to 80 weight percent, still more specifically 64 to74 weight percent. In other embodiments, the reaction product amount is52 to 80 weight percent, specifically 53 to 70 weight percent, morespecifically 53 to 63 weight percent. In still other embodiments, thereaction product amount is 5 to 20 weight percent, specifically 5 to 15weight percent, more specifically 7 to 13 weight percent. In yet otherembodiments, the reaction product amount is 0.5 to 5 weight percent,specifically 1 to 3 weight percent.

In some embodiments, particularly those in which the amount of thepoly(phenylene ether)-polysiloxane block copolymer reaction product isless than 50 weight percent, it can be beneficial to include a secondpoly(phenylene ether) in the composition. As used herein, the term“second poly(phenylene ether)” refers to a poly(phenylene ether) that isnot derived from the poly(phenylene ether)-polysiloxane block copolymerreaction. The second poly(phenylene ether) can be chemically the same asor different from the first poly(phenylene ether). Suitable first andsecond poly(phenylene ether)s include those comprising repeatingstructural units having the formula

wherein each occurrence of Z¹ is independently halogen, unsubstituted orsubstituted C₁-C₁₂ hydrocarbyl provided that the hydrocarbyl group isnot tertiary hydrocarbyl, C₁-C₁₂ hydrocarbylthio, C₁-C₁₂ hydrocarbyloxy,or C₂-C₁₂ halohydrocarbyloxy wherein at least two carbon atoms separatethe halogen and oxygen atoms; and each occurrence of Z² is independentlyhydrogen, halogen, unsubstituted or substituted C₁-C₁₂ hydrocarbylprovided that the hydrocarbyl group is not tertiary hydrocarbyl, C₁-C₁₂hydrocarbylthio, C₁-C₁₂ hydrocarbyloxy, or C₂-C₁₂ halohydrocarbyloxywherein at least two carbon atoms separate the halogen and oxygen atoms.As used herein, the term “hydrocarbyl”, whether used by itself, or as aprefix, suffix, or fragment of another term, refers to a residue thatcontains only carbon and hydrogen. The residue can be aliphatic oraromatic, straight-chain, cyclic, bicyclic, branched, saturated, orunsaturated. It can also contain combinations of aliphatic, aromatic,straight chain, cyclic, bicyclic, branched, saturated, and unsaturatedhydrocarbon moieties. However, when the hydrocarbyl residue is describedas substituted, it may, optionally, contain heteroatoms over and abovethe carbon and hydrogen members of the substituent residue. Thus, whenspecifically described as substituted, the hydrocarbyl residue can alsocontain one or more carbonyl groups, amino groups, hydroxyl groups, orthe like, or it can contain heteroatoms within the backbone of thehydrocarbyl residue. As one example, Z¹ can be a di-n-butylaminomethylgroup formed by reaction of a terminal 3,5-dimethyl-1,4-phenyl groupwith the di-n-butylamine component of an oxidative polymerizationcatalyst.

In some embodiments, the second poly(phenylene ether) has an intrinsicviscosity of 0.2 to 1 deciliter per gram measured by Ubbelohdeviscometer at 25° C. in chloroform. Within this range, the secondpoly(phenylene ether) intrinsic viscosity can be 0.2 to 0.5 deciliterper gram, specifically 0.2 to 0.4 deciliter per gram, still morespecifically 0.25 to 0.35 deciliter per gram.

In some embodiments, the second poly(phenylene ether) comprises2,6-dimethyl-1,4-phenylene ether units, 2,3,6-trimethyl-1,4-phenyleneether units, or a combination thereof. In some embodiments, the secondpoly(phenylene ether) comprises a poly(2,6-dimethyl-1,4-phenyleneether). In some embodiments, the second poly(phenylene ether) comprisesa poly(2,6-dimethyl-1,4-phenylene ether) having an intrinsic viscosityof 0.2 to 0.4 deciliter per gram, specifically 0.25 to 0.35 deciliterper gram, measured by Ubbelohde viscometer at 25° C. in chloroform.

When present, the second poly(phenylene ether) can be used in an amountof 5 to 90.5 weight percent, specifically 20 to 80 weight percent, morespecifically 50 to 70 weight percent, based on the total weight of thecomposition.

In addition to the poly(phenylene ether)-polysiloxane block copolymerreaction product and the optional second poly(phenylene ether), thecomposition comprises a flame retardant. The flame retardant comprisesan organophosphate ester, a phosphazene, or a combination thereof.

In some embodiments, the flame retardant comprises or consists of anorganophosphate ester. Exemplary organophosphate ester flame retardantsinclude phosphate esters comprising phenyl groups, substituted phenylgroups, or a combination of phenyl groups and substituted phenyl groups,bis-aryl phosphate esters based upon resorcinol such as, for example,resorcinol bis(diphenyl phosphate), as well as those based uponbisphenols such as, for example, bisphenol A bis(diphenyl phosphate). Insome embodiments, the organophosphate ester is selected fromtris(alkylphenyl) phosphates (for example, CAS Reg. No. 89492-23-9 orCAS Reg. No. 78-33-1), resorcinol bis(diphenyl phosphate) (CAS Reg. No.57583-54-7), bisphenol A bis(diphenyl phosphate) (CAS Reg. No.181028-79-5), triphenyl phosphate (CAS Reg. No. 115-86-6),tris(isopropylphenyl) phosphates (for example, CAS Reg. No. 68937-41-7),and combinations thereof.

In some embodiments the organophosphate ester comprises or consists of abis-aryl phosphate having the formula

wherein R is independently at each occurrence a C₁-C₁₂ alkylene group;R⁹ and R¹⁰ are independently at each occurrence a C₁-C₅ alkyl group; R⁵,R⁶, and R⁸ are independently a C₁-C₁₂ hydrocarbyl group; R⁷ isindependently at each occurrence a C₁-C₁₂ hydrocarbyl group; n is 1 to25; and s1 and s2 are independently an integer equal to 0, 1, or 2. Insome embodiments OR⁵, OR⁶, OR⁷ and OR⁸ are independently derived fromphenol, a monoalkylphenol, a dialkylphenol, or a trialkylphenol.

As readily appreciated by one of ordinary skill in the art, the bis-arylphosphate is derived from a bisphenol. Exemplary bisphenols include2,2-bis(4-hydroxyphenyl)propane (bisphenol A),2,2-bis(4-hydroxy-3-methylphenyl)propane, bis(4-hydroxyphenyl)methane,bis(4-hydroxy-3,5-dimethylphenyl)methane and1,1-bis(4-hydroxyphenyl)ethane. In some embodiments, the bisphenolcomprises bisphenol A.

In some embodiments, the flame retardant comprises a phosphazene. Aphosphazene is a compound comprising repeating units having thestructure

wherein each occurrence of R¹⁹ is independently C₁-C₆ alkoxy,unsubstituted or substituted phenoxy, or unsubstituted or substitutednaphthyloxy. When present, the substituents on the phenoxy ornaphthyloxy groups can be, for example, C₁-C₆ alkyl, C₁-C₆ alkoxy, orphenyl.

In some embodiments, the phosphazene comprises a cyclic phosphazenehaving the structure

wherein R¹⁹ is defined above and a is 3 to 12, specifically 3 to 6. Insome embodiments, a is 3 and each occurrence of R¹⁹ is unsubstitutedphenoxy.

In some embodiments, the phosphazene comprises a linear polyphosphazenehaving the structure

wherein R¹⁹ is defined above; b is 3 to 1,000; A is —N═P(O)(R¹⁹) or—N═P(R¹⁹)₃; and B is —P(R¹⁹)₄ or —P(O)(R¹⁹)₂.

The phosphazene can be crosslinked with a phenylene group, a biphenylenegroup, or a group having the structure

wherein X is C₁-C₆ alkylidene, O, S, or SO₂.

A mixture of at least two of cyclic phosphazenes, linearpolyphosphazenes, and crosslinked phosphazenes can be used. In someembodiments, the phosphazene comprises at last 80 weight percent cyclicphosphazenes, based on the weight of the phosphazene.

Methods for making phosphazenes are known, and phosphazenes arecommercially available as, for example, RABITLE™ FP-100 and RABITLE™FP-110 from Fushimi Pharmaceutical Co., Ltd., IDB-Poretar-201 fromID-Biochem, and SPB-100 from Otsuka Chemical Company.

The amount of the organophosphate ester, phosphazene, or combinationthereof can be 1 to 25 weight percent, based on the total weight of thecomposition. In some embodiments, the amount of the organophosphateester, phosphazene, or combination thereof is 4 to 15 weight percent,specifically 4 to 12 weight percent, more specifically 4 to 10 weightpercent. In other embodiments, the amount of the organophosphate ester,phosphazene, or combination thereof is 10 to 25 weight percent,specifically 15 to 25 weight percent.

In addition to the organophosphate ester and/or phosphazene, the flameretardant can, optionally, further comprise a dialkylphosphinate salt.As used herein, the term “dialkylphosphinate salt” refers to a saltcomprising at least one cation and at least one dialkylphosphinateanion. In some embodiments, the dialkylphosphinate salt has the formula

wherein R^(a) and R^(b) are each independently C₁-C₆ alkyl; M iscalcium, magnesium, aluminum, zinc, ammonium, or hydrocarbyl-substitutedammonium; and d is 2 or 3. Examples of R^(a) and R^(b) include methyl,ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl, and phenyl.In some embodiments, R^(a) and R^(b) are ethyl, M is aluminum, and d is3 (that is, the dialkylphosphinate salt is aluminumtris(diethylphosphinate)).

In some embodiments, the dialkylphosphinate salt is in particulate form.The dialkylphosphinate salt particles can have a median particlediameter (D50) less than or equal to 40 micrometers, or, morespecifically, a D50 less than or equal to 30 micrometers, or, even morespecifically, a D50 less than or equal to 25 micrometers. Additionally,the dialkylphosphinate salt can be combined with a polymer, such as thepoly(phenylene ether)-polysiloxane block copolymer reaction product, thesecond poly(phenylene ether), or combination thereof, to form amasterbatch. The dialkylphosphinate salt masterbatch comprises thedialkylphosphinate salt in an amount greater than is present in thethermoplastic composition. Employing a masterbatch for the addition ofthe dialkylphosphinate salt to the other components of the compositioncan facilitate addition and improve distribution of thedialkylphosphinate salt.

In some embodiments, the dialkylphosphinate salt is used in an amount of1 to 5 weight percent, specifically 1 to 3 weight percent, based on thetotal weight of the composition. When the amount of the organophosphateester, phosphazene, or combination thereof is less than 4 weightpercent, then the amount of dialkylphosphinate salt is sufficient tomake the total flame retardant amount at least 4 weight percent. In someembodiments the composition comprises less than or equal to 1 weightpercent of dialkylphosphinate salt, based on the total weight of thecomposition. In some embodiments the composition excludesdialkylphosphinate salt.

The composition comprises 4 to 25 weight percent of the flame retardant,based on the total weight of the composition. In some embodiments, theflame retardant amount is 4 to 15 weight percent, specifically 4 to 12weight percent, more specifically 4 to 10 weight percent. In otherembodiments, the flame retardant amount is 10 to 25 weight percent,specifically 15 to 25 weight percent.

In addition to the poly(phenylene ether)-polysiloxane block copolymerreaction product, the optional second poly(phenylene ether), and theflame retardant, the composition comprises a reinforcing filler.Reinforcing fillers include, for example, glass fibers, carbon fibers,wollastonite, halloysite, clays, talcs, micas, glass flakes, solid glassbeads, hollow glass beads, solid ceramic beads, hollow ceramic beads,and combinations thereof. In some embodiments, the reinforcing fillercomprises or consists of glass fibers.

Suitable glass fibers include those based on E, A, C, ECR, R, S, D, andNE glasses, as well as quartz. In some embodiments, the glass fiber hasa diameter of 2 to 30 micrometers, specifically 5 to 25 micrometers,more specifically 10 to 15 micrometers. In some embodiments, the lengthof the glass fibers before compounding is 2 to 7 millimeters,specifically 3 to 5 millimeters. Suitable glass fiber is commerciallyavailable from suppliers including, for example, Owens Corning, NipponElectric Glass, PPG, and Johns Manville.

The reinforcing filler can, optionally, include an adhesion promoter toimprove its compatibility with the poly(phenylene ether)-polysiloxaneblock copolymer reaction product. Adhesion promoters include chromiumcomplexes, silanes, titanates, zircoaluminates, propylene maleicanhydride copolymers, reactive cellulose esters, and the like.

The reinforcing filler can be used in an amount of 5 to 40 weightpercent, based on the total weight of the composition. In someembodiments, the reinforcing filler amount is 8 to 30 weight percent,specifically 15 to 25 weight percent. In other embodiments, thereinforcing filler amount is 10 to 30 weight percent, specifically 15 to25 weight percent.

The composition can, optionally, further include an impact modifier.Impact modifiers include, for example, rubber-modified polystyrenes,unhydrogenated block copolymers of an alkenyl aromatic monomer and aconjugated diene, hydrogenated block copolymers of an alkenyl aromaticmonomer and a conjugated diene, acrylate core-shell impact modifiers(e.g., those having a crosslinked poly(butyl acrylate) core and agrafted poly(methyl methacrylate) shell), and combinations thereof.

The impact modifier can include a rubber-modified polystyrene.Rubber-modified polystyrene comprises polystyrene and polybutadiene.Rubber-modified polystyrenes are sometimes referred to as “high-impactpolystyrenes” or “HIPS”. In some embodiments, the rubber-modifiedpolystyrene comprises 80 to 96 weight percent polystyrene, specifically88 to 94 weight percent polystyrene; and 4 to 20 weight percentpolybutadiene, specifically 6 to 12 weight percent polybutadiene, basedon the weight of the rubber-modified polystyrene. Suitablerubber-modified polystyrenes are commercially available as, for example,HIPS3190 from SABIC Innovative Plastics.

The impact modifier can include an unhydrogenated block copolymer of analkenyl aromatic compound and a conjugated diene. For brevity, thiscomponent is referred to as an “unhydrogenated block copolymer”. Theunhydrogenated block copolymer can comprise 10 to 90 weight percent ofpoly(alkenyl aromatic) content and 90 to 10 weight percent ofpoly(conjugated diene) content, based on the weight of theunhydrogenated block copolymer. In some embodiments, the unhydrogenatedblock copolymer is a low poly(alkenyl aromatic content) unhydrogenatedblock copolymer in which the poly(alkenyl aromatic) content is 10 toless than 40 weight percent, specifically 20 to 35 weight percent, morespecifically 25 to 35 weight percent, yet more specifically 30 to 35weight percent, all based on the weight of the low poly(alkenylaromatic) content unhydrogenated block copolymer. In other embodiments,the unhydrogenated block copolymer is a high poly(alkenyl aromatic)content unhydrogenated block copolymer in which the poly(alkenylaromatic) content is 40 to 90 weight percent, specifically 50 to 80weight percent, more specifically 60 to 70 weight percent, all based onthe weight of the high poly(alkenyl aromatic) content unhydrogenatedblock copolymer.

In some embodiments, the unhydrogenated block copolymer has a weightaverage molecular weight of 40,000 to 400,000 atomic mass units. Thenumber average molecular weight and the weight average molecular weightcan be determined by gel permeation chromatography and based oncomparison to polystyrene standards. In some embodiments, theunhydrogenated block copolymer has a weight average molecular weight of200,000 to 400,000 atomic mass units, specifically 220,000 to 350,000atomic mass units. In other embodiments, the unhydrogenated blockcopolymer has a weight average molecular weight of 40,000 to 200,000atomic mass units, specifically 40,000 to 180,000 atomic mass units,more specifically 40,000 to 150,000 atomic mass units.

The alkenyl aromatic monomer used to prepare the unhydrogenated blockcopolymer can have the structure

wherein R¹¹ and R¹² each independently represent a hydrogen atom, aC₁-C₈ alkyl group, or a C₂-C₈ alkenyl group; R¹³ and R¹⁷ eachindependently represent a hydrogen atom, a C₁-C₈ alkyl group, a chlorineatom, or a bromine atom; and R¹⁴, R¹⁵, and R¹⁶ each independentlyrepresent a hydrogen atom, a C₁-C₈ alkyl group, or a C₂-C₈ alkenylgroup, or R¹⁴ and R¹⁵ are taken together with the central aromatic ringto form a naphthyl group, or R¹⁵ and R¹⁶ are taken together with thecentral aromatic ring to form a naphthyl group. Specific alkenylaromatic monomers include, for example, styrene, chlorostyrenes such asp-chlorostyrene, methylstyrenes such as alpha-methylstyrene andp-methylstyrene, and t-butylstyrenes such as 3-t-butylstyrene and4-t-butylstyrene. In some embodiments, the alkenyl aromatic monomer isstyrene.

The conjugated diene used to prepare the unhydrogenated block copolymercan be a C₄-C₂₀ conjugated diene. Suitable conjugated dienes include,for example, 1,3-butadiene, 2-methyl-1,3-butadiene,2-chloro-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene,1,3-hexadiene, and combinations thereof. In some embodiments, theconjugated diene is 1,3-butadiene, 2-methyl-1,3-butadiene, or acombination thereof. In some embodiments, the conjugated diene consistsof 1,3-butadiene.

The unhydrogenated block copolymer is a copolymer comprising (A) atleast one block derived from an alkenyl aromatic compound and (B) atleast one block derived from a conjugated diene. The arrangement ofblocks (A) and (B) includes a linear structure, a grafted structure, anda radial teleblock structure with or without a branched chain. Linearblock copolymers include tapered linear structures and non-taperedlinear structures. In some embodiments, the unhydrogenated blockcopolymer has a tapered linear structure. In some embodiments, theunhydrogenated block copolymer has a non-tapered linear structure. Insome embodiments, the unhydrogenated block copolymer comprises a (B)block that comprises random incorporation of alkenyl aromatic monomer.Linear block copolymer structures include diblock (A-B block), triblock(A-B-A block or B-A-B block), tetrablock (A-B-A-B block), and pentablock(A-B-A-B-A block or B-A-B-A-B block) structures as well as linearstructures containing 6 or more blocks in total of (A) and (B), whereinthe molecular weight of each (A) block can be the same as or differentfrom that of other (A) blocks, and the molecular weight of each (B)block can be the same as or different from that of other (B) blocks. Insome embodiments, the unhydrogenated block copolymer is a diblockcopolymer, a triblock copolymer, or a combination thereof.

In some embodiments, the unhydrogenated block copolymer excludes theresidue of monomers other than the alkenyl aromatic compound and theconjugated diene. In some embodiments, the unhydrogenated blockcopolymer consists of blocks derived from the alkenyl aromatic compoundand the conjugated diene. It does not comprise grafts formed from theseor any other monomers. It also consists of carbon and hydrogen atoms andtherefore excludes heteroatoms.

In some embodiments, the unhydrogenated block copolymer includes theresidue of one or more acid functionalizing agents, such as maleicanhydride.

In some embodiments, the unhydrogenated block copolymer comprises apolystyrene-polybutadiene-polystyrene triblock copolymer. In someembodiments, the unhydrogenated block copolymer comprises apolystyrene-polyisoprene-polystyrene triblock copolymer.

Methods for preparing unhydrogenated block copolymers are known in theart and unhydrogenated block copolymers are commercially available.Illustrative commercially available unhydrogenated block copolymersinclude the polystyrene-polybutadiene-polystyrene triblock copolymersfrom Kraton Performance Polymers Inc. under the trade names Kraton™D1101 and D1102; and the styrene-butadiene radial teleblock copolymersfrom Chevron Phillips Chemical Company under the trade names K-RESIN™KK38, KR01, KR03, and KR05.

The impact modifier can be a hydrogenated block copolymer of an alkenylaromatic compound and a conjugated diene. For brevity, this component isreferred to as a “hydrogenated block copolymer”. The hydrogenated blockcopolymer is the same as the unhydrogenated block copolymer, except thatin the hydrogenated block copolymer the aliphatic unsaturated groupcontent in the block (B) derived from a conjugated diene has been atleast partially reduced by hydrogenation. In some embodiments, thealiphatic unsaturation in the (B) block is reduced by at least 50percent, specifically at least 70 percent, more specifically at least 90percent.

Illustrative commercially available hydrogenated block copolymersinclude the polystyrene-poly(ethylene-propylene) diblock copolymersavailable from Kraton Performance Polymers Inc. as KRATON™ G1701 andG1702; the polystyrene-poly(ethylene-butylene)-polystyrene triblockcopolymers available from Kraton Performance Polymers Inc. as KRATON™G1641, G1650, G1651, G1654, G1657, G1726, G4609, G4610, GRP-6598,MD-6932M, MD-6933, and MD-6939; thepolystyrene-poly(ethylene-propylene)-polystyrene triblock copolymersavailable from Kraton Performance Polymers Inc. as KRATON™ G1730; themaleic anhydride-grafted polystyrene-poly(ethylene-butylene)-polystyrenetriblock copolymers available from Kraton Performance Polymers Inc. asKRATON™ G1901, G1924, and MD-6684; the maleic anhydride-graftedpolystyrene-poly(ethylene-butylene-styrene)-polystyrene triblockcopolymer available from Kraton Performance Polymers Inc. as KRATON™MD-6670; the polystyrene-poly(ethylene-butylene)-polystyrene triblockcopolymer comprising 67 weight percent polystyrene available from AsahiKasei Elastomer as TUFTEC™ H1043; thepolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymercomprising 42 weight percent polystyrene available from Asahi KaseiElastomer as TUFTEC™ H1051; thepolystyrene-poly(butadiene-butylene)-polystyrene triblock copolymersavailable from Asahi Kasei Elastomer as TUFTEC™ P1000 and P2000; thepolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymercomprising 60 weight polystyrene available from Kuraray as SEPTON™S8104; the polystyrene-poly(ethylene-ethylene/propylene)-polystyrenetriblock copolymers available from Kuraray as SEPTON™ S4044, S4055,S4077, and S4099; and thepolystyrene-poly(ethylene-propylene)-polystyrene triblock copolymercomprising 65 weight percent polystyrene available from Kuraray asSEPTON™ S2104.

In some embodiments, the impact modifier is apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymerhaving a polystyrene content of 25 to 35 weight percent and a weightaverage molecular weight of 200,000 to 400,000 atomic mass units.

When present, the impact modifier can be used in an amount of 2 to 10weight percent, specifically 3 to 6 weight percent, based on the totalweight of the composition.

The composition can, optionally, further comprise a hydrocarbon resin.Examples of hydrocarbon resins are aliphatic hydrocarbon resins,hydrogenated aliphatic hydrocarbon resins, aliphatic/aromatichydrocarbon resins, hydrogenated aliphatic/aromatic hydrocarbon resins,cycloaliphatic hydrocarbon resins, hydrogenated cycloaliphatic resins,cycloaliphatic/aromatic hydrocarbon resins, hydrogenatedcycloaliphatic/aromatic hydrocarbon resins, hydrogenated aromatichydrocarbon resins, terpene resins, hydrogenated terpene resins,terpene-phenol resins, rosins, and rosin esters, hydrogenated rosins androsin esters, and mixtures thereof. As used herein, “hydrogenated”, whenreferring to the hydrocarbon resin, includes fully, substantially, andpartially hydrogenated resins. Suitable aromatic resins include aromaticmodified aliphatic resins, aromatic modified cycloaliphatic resins, andhydrogenated aromatic hydrocarbon resins having an aromatic content of 1to 30 weight percent. Any of the above resins can be grafted with anunsaturated ester or anhydride using methods known in the art. Suchgrafting can provide enhanced properties to the resin. In someembodiments, the hydrocarbon resin is a hydrogenated aromatichydrocarbon resin.

Suitable hydrocarbon resins are commercially available and include, forexample, EMPR™ 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,116, 117, and 118 resins, and OPPERA™ resins, available from ExxonMobilChemical Company; ARKON™ P140, P125, P115, M115, and M135, and SUPERESTER™ rosin esters available from Arakawa Chemical Company of Japan;SYLVARES™ polyterpene resins, styrenated terpene resins and terpenephenolic resins available from Arizona Chemical Company; SYLVATAC™ andSYLVALITE™ rosin esters available from Arizona Chemical Company;NORSOLENE™ aliphatic aromatic resins available from Cray Valley;DERTOPHENE™ terpene phenolic resins and DERCOLYTE™ polyterpene resinsavailable from DRT Chemical Company; EASTOTAC™ resins, PICCOTAC™ resins,REGALITE™ and REGALREZ™ hydrogenated cycloaliphatic/aromatic resins, andPICCOLYTE™ and PERMALYN™ polyterpene resins, rosins, and rosin estersavailable from Eastman Chemical Company; WINGTACK™ resins available fromGoodyear Chemical Company; coumarone/indene resins available fromNeville Chemical Company; QUINTONE™ acid modified C5 resins, C5/C9resins, and acid-modified C5/C9 resins available from Nippon Zeon; andCLEARON™ hydrogenated terpene resins available from Yasuhara. In someembodiments, the hydrocarbon resin is a hydrogenated terpene resin. Insome embodiments, the hydrocarbon resin is a saturated polyalicyclichydrocarbon resin.

The hydrocarbon resin can have a softening point of at least 120° C.measured according to ASTM E28. Specifically, the softening point can be120 to 180° C., specifically 130 to 170° C., more specifically 140 to160° C. In some embodiments, the hydrocarbon resin comprises ahydrogenated alicyclic hydrocarbon resin, a hydrogenated terpene resin,or a combination thereof. In some embodiments, the hydrocarbon resincomprises a hydrogenated alicyclic hydrocarbon resin having a softeningpoint of 120 to 135° C. An example of such a resin is ARKON™ P125 havinga softening point of about 125° C., available from Arakawa ChemicalCompany, In some embodiments, the hydrocarbon resin comprises ahydrogenated alicyclic hydrocarbon resin having a softening point of 135to 145° C. An example of such a resin is ARKON™ P140 having a softeningpoint of about 140° C., available from Arakawa Chemical Company, In someembodiments, the hydrocarbon resin comprises a hydrogenated terpeneresin having a softening point of 145 to 160° C. An example of such aresin is CLEARON™ P150 available from Yasuhara.

When present, the hydrocarbon resin can be used in an amount of 1 to 8weight percent, specifically 2 to 6 weight percent, based on the totalweight of the composition.

The composition can, optionally, further comprise a trihydrocarbylphosphite. Trihydrocarbyl phosphites have the general structureP(OR¹⁸)₃, wherein each occurrence of R¹⁸ is independently C₁-C₁₈hydrocarbyl. In some embodiments, each R¹⁸ is independently C₆-C₁₈alkyl. In other embodiments, at least one R¹⁸ is C₆-C₁₈ aryl. In someembodiments, each occurrence of R¹⁸ is independently an unsubstituted orsubstituted C₆-C₁₈ aryl. Suitable trihydrocarbyl phosphites include, forexample, trioctyl phosphite, tridecyl phosphite, tridodecyl phosphite,phenyl didecyl phosphite, decyl diphenyl phosphite, triphenyl phosphite,tritolyl phosphites, tris(2,4-di-tert-butylphenyl)phosphite,bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, and the like,and combinations thereof. Suitable trihydrocarbyl phosphites furtherinclude spiro diphosphites such as, for example,3,9-bis[2,4-bis(1,1-dimethylethyl)phenoxy]-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane(CAS Reg. No. 26741-53-7; commercially available from Ciba under thetrade name IRGAFOS™ 126). In some embodiments, the aryl phosphitecomprises tris(2,4-di-tert-butylphenyl)phosphite (CAS Reg. No.31570-04-4). In some embodiments, the aryl phosphite comprisesbis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite (CAS Reg. No.26741-53-7).

When present, the trihydrocarbyl phosphite can be used in an amount of0.05 to 1 weight percent, specifically 0.1 to 0.5 weight percent, basedon the total weight of the composition.

The composition can, optionally, further comprise linear low densitypolyethylene (LLDPE). Linear low density polyethylene is a copolymer ofethylene and a longer chain olefin such as 1-butene, 1-hexene, or1-octene. In some embodiments, the linear low density polyethylene is acopolymer of ethylene and 1-butene. Linear low density polyethylenetypically has a density of about 0.92 grams/centimeter³. When present,the linear low density polyethylene can be used in an amount of 0.5 to 5weight percent, specifically 1 to 3 weight percent, based on the totalweight of the composition.

The composition can, optionally, further comprise one or more additivesknown in the thermoplastics art. For example, the composition can,optionally, further comprise an additive chosen from stabilizers, moldrelease agents, lubricants, processing aids, drip retardants, nucleatingagents, UV blockers, dyes, pigments, antioxidants, anti-static agents,blowing agents, mineral oil, metal deactivators, antiblocking agents,and the like, and combinations thereof. When present, such additives aretypically used in a total amount of less than or equal to 5 weightpercent, specifically less than or equal to 4 weight percent, morespecifically less than or equal to 3 weight percent, based on the totalweight of the composition.

The composition can, optionally, exclude polymers other than thoserequired. For example, the composition can comprise less than or equalto 1 weight percent of each of polyamides and polyesters. In someembodiments, the composition comprises less than or equal to 4 weightpercent, specifically less than or equal to 3 weight percent, morespecifically less than or equal to 2 weight percent, of polyolefins. Insome embodiments, the composition comprises less than or equal to 1weight percent of polyolefins other than linear low densitypolyethylene. In other embodiments, the composition comprises less thanor equal to 1 weight percent of any polyolefins.

One advantage of the composition is that it can achieve a UL 94 V-0rating without using the halogenated flame retardants that are typicallyemployed in glass-filled polyester compositions utilized for similarproduct applications. Thus, the composition can comprise less than orequal to 0.1 weight percent halogens, specifically less than or equal to0.01 weight percent halogens, based on the total weight of thecomposition. In some embodiments, composition is halogen-free.

In a very specific embodiment of the composition, the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 64 to 74 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the flame retardant comprises (or consists of) of anorganophosphate ester; the composition comprises 4 to 10 weight percentof the flame retardant; the reinforcing filler comprises (or consistsof) glass fibers; the composition comprises 15 to 25 weight percent ofthe reinforcing filler; the composition further comprises 2 to 8 weightpercent of a polystyrene-poly(ethylene-butylene)-polystyrene triblockcopolymer; and the composition comprises less than or equal to 1 weightpercent of each of polyamides and polyesters.

In another very specific embodiment of the composition, thepoly(phenylene ether)-polysiloxane block copolymer comprises apoly(phenylene ether) block comprising phenylene ether repeating unitshaving the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 53 to 63 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the flame retardant comprises (or consists of) anorganophosphate ester; the composition comprises 15 to 25 weight percentof the flame retardant; the reinforcing filler comprises (or consistsof) glass fibers; the composition comprises 15 to 25 weight percent ofthe reinforcing filler; and the composition comprises less than or equalto 1 weight percent of each of polyamides and polyesters.

In another very specific embodiment of the composition, thepoly(phenylene ether)-polysiloxane block copolymer comprises apoly(phenylene ether) block comprising phenylene ether repeating unitshaving the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 5 to 15 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the composition further comprises 47 to 67 weight percent of asecond poly(phenylene ether) comprising a homopolymer of2,6-dimethylphenol; the flame retardant comprises an organophosphateester; the composition comprises 6 to 14 weight percent of the flameretardant; the reinforcing filler comprises glass fibers; thecomposition comprises 15 to 25 weight percent of the reinforcing filler;the composition further comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andthe composition comprises less than or equal to 1 weight percent of eachof polyamides and polyesters.

In another very specific embodiment of the composition, thepoly(phenylene ether)-polysiloxane block copolymer comprises apoly(phenylene ether) block comprising phenylene ether repeating unitshaving the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 0.5 to 5 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the composition further comprises 50 to 70 weight percent of asecond poly(phenylene ether) comprising a homopolymer of2,6-dimethylphenol; the flame retardant comprises the organophosphateester; the composition comprises 6 to 14 weight percent of the flameretardant; the reinforcing filler comprises glass fibers; thecomposition comprises 15 to 25 weight percent of the reinforcing filler;the composition further comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andthe composition comprises less than or equal to 1 weight percent of eachof polyamides and polyesters.

In another very specific embodiment of the composition, thepoly(phenylene ether)-polysiloxane block copolymer comprises apoly(phenylene ether) block comprising phenylene ether repeating unitshaving the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 0.5 to 5 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the composition further comprises 50 to 70 weight percent of asecond poly(phenylene ether) comprising a homopolymer of2,6-dimethylphenol; the flame retardant comprises the organophosphateester; the composition comprises 6 to 14 weight percent of the flameretardant; the reinforcing filler comprises glass fibers; thecomposition comprises 15 to 25 weight percent of the reinforcing filler;the composition further comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andthe composition comprises less than or equal to 1 weight percent of eachof polyamides and polyesters.

In another very specific embodiment of the composition, thepoly(phenylene ether)-polysiloxane block copolymer comprises apoly(phenylene ether) block comprising phenylene ether repeating unitshaving the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 53 to 63 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the flame retardant comprises the organophosphate ester; thecomposition comprises 15 to 25 weight percent of the flame retardant;the reinforcing filler comprises glass fibers; the composition comprises15 to 25 weight percent of the reinforcing filler; and the compositioncomprises less than or equal to 1 weight percent of each of polyamidesand polyesters, and less than or equal to 3 weight percent ofpolyolefins.

The composition is useful for molding articles. Thus, one embodiment isan article comprising a composition, comprising: 0.5 to 91 weightpercent of a poly(phenylene ether)-polysiloxane block copolymer reactionproduct comprising a first poly(phenylene ether) and a poly(phenyleneether)-polysiloxane block copolymer; 4 to 25 weight percent of a flameretardant comprising an organophosphate ester, a phosphazene, or acombination thereof; and 5 to 40 weight percent of a reinforcing filler;wherein all weight percents are based on the total weight of thecomposition. The composition is particularly useful for molding articlesincluding electrophotographic copier parts such as fuser holders, andparts for electrical components, such as photovoltaic junction boxes andconnectors, inverter housings, automotive electrical connectors,electrical relays, and charge couplers. Other than their beingfabricated with the present composition, such articles are known, as aremethods for their fabrication. For example, U.S. Pat. No. 5,499,087 ofHiraoka et al. describes a fuser holder for an electrophotographiccopier. Suitable methods of forming such articles include single layerand multilayer sheet extrusion, injection molding, blow molding, filmextrusion, profile extrusion, pultrusion, compression molding,thermoforming, pressure forming, hydroforming, vacuum forming, and thelike. Combinations of the foregoing article fabrication methods can beused. In some embodiments, the article is formed by injection molding.

The compositional variations described above apply as well to articlescomprising the composition.

In a very specific embodiment of the article, the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 64 to 74 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the flame retardant comprises an organophosphate ester; thecomposition comprises 4 to 10 weight percent of the flame retardant; thereinforcing filler comprises glass fibers; the composition comprises 15to 25 weight percent of the reinforcing filler; the composition furthercomprises 2 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andthe composition comprises less than or equal to 1 weight percent of eachof polyamides and polyesters.

In another very specific embodiment of the article, the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; wherein the composition comprises 53 to 63 weightpercent of the poly(phenylene ether)-polysiloxane block copolymerreaction product; the flame retardant comprises an organophosphateester; the composition comprises 15 to 25 weight percent of the flameretardant; the reinforcing filler comprises glass fibers; thecomposition comprises 15 to 25 weight percent of the reinforcing filler;and the composition comprises less than or equal to 1 weight percent ofeach of polyamides and polyesters.

In another very specific embodiment of the article, the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 5 to 15 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the composition further comprises 47 to 67 weight percent of asecond poly(phenylene ether) comprising a homopolymer of2,6-dimethylphenol; the flame retardant comprises an organophosphateester; the composition comprises 6 to 14 weight percent of the flameretardant; the reinforcing filler comprises glass fibers; thecomposition comprises 15 to 25 weight percent of the reinforcing filler;the composition further comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andthe composition comprises less than or equal to 1 weight percent of eachof polyamides and polyesters.

In another very specific embodiment of the article, the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 0.5 to 5 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the composition further comprises 50 to 70 weight percent of asecond poly(phenylene ether) comprising a homopolymer of2,6-dimethylphenol; the flame retardant comprises the organophosphateester; the composition comprises 6 to 14 weight percent of the flameretardant; the reinforcing filler comprises glass fibers; thecomposition comprises 15 to 25 weight percent of the reinforcing filler;the composition further comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andthe composition comprises less than or equal to 1 weight percent of eachof polyamides and polyesters.

In another very specific embodiment of the article, the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; the composition comprises 53 to 63 weight percentof the poly(phenylene ether)-polysiloxane block copolymer reactionproduct; the flame retardant comprises the organophosphate ester; thecomposition comprises 15 to 25 weight percent of the flame retardant;the reinforcing filler comprises glass fibers; the composition comprises15 to 25 weight percent of the reinforcing filler; and the compositioncomprises less than or equal to 1 weight percent of each of polyamidesand polyesters, and less than or equal to 3 weight percent ofpolyolefins.

The invention includes at least the following embodiments.

Embodiment 1

A composition, comprising: 0.5 to 91 weight percent of a poly(phenyleneether)-polysiloxane block copolymer reaction product comprising a firstpoly(phenylene ether) and a poly(phenylene ether)-polysiloxane blockcopolymer; 4 to 25 weight percent of a flame retardant comprising anorganophosphate ester, a phosphazene, or a combination thereof; and 5 to40 weight percent of a reinforcing filler; wherein all weight percentsare based on the total weight of the composition.

Embodiment 2

The composition of embodiment 1, exhibiting a flammability rating of V-0at a sample thickness less than or equal to 1.5 millimeters in the 20millimeter Vertical Burning Flame Test of Underwriter's LaboratoryBulletin 94 “Tests for Flammability of Plastic Materials, UL 94”, a heatdeflection temperature of at least 110° C. determined according to ASTMD 648-07 using a stress of 1.82 megapascals (MPa) and a sample thicknessof 6.4 millimeters, and a flexural modulus of at least 3,500 megapascalsmeasured at 23° C. according to ASTM D 790-07e1 using a sample thicknessof 6.4 millimeters.

Embodiment 3 The composition of embodiment 1 or 2, further comprising 5to 90.5 weight percent of a second poly(phenylene ether). Embodiment 4

The composition of embodiment 3, comprising 0.5 to 5 weight percent ofthe poly(phenylene ether)-polysiloxane block copolymer reaction product,and 30 to 90.5 weight percent of the second poly(phenylene ether).

Embodiment 5

The composition of any of embodiments 1-4, wherein the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60.

Embodiment 6

The composition of any of embodiments 1-5, wherein the poly(phenyleneether)-polysiloxane block copolymer contributes 0.025 to 5 weightpercent of polysiloxane to the composition.

Embodiment 7

The composition of any of embodiments 1-6, wherein the flame retardantcomprises an organophosphate ester.

Embodiment 8

The composition of any of embodiments 1-7, wherein the flame retardantcomprises a phosphazene.

Embodiment 9

The composition of any of embodiments 1-8, wherein the reinforcingfiller is selected from the group consisting of glass fibers, carbonfibers, wollastonite, halloysite, clays, talcs, micas, glass flakes,solid glass beads, hollow glass beads, solid ceramic beads, hollowceramic beads, and combinations thereof.

Embodiment 10

The composition of any of embodiments 1-9, wherein the reinforcingfiller comprises glass fibers.

Embodiment 11

The composition of any of embodiments 1-10, further comprising 2 to 10weight percent of an impact modifier selected from the group consistingof rubber-modified polystyrenes, unhydrogenated block copolymers of analkenyl aromatic monomer and a conjugated diene, hydrogenated blockcopolymers of an alkenyl aromatic monomer and a conjugated diene,acrylate core-shell impact modifiers, and combinations thereof.

Embodiment 12

The composition of any of embodiments 1-11, further comprising 1 to 8weight percent of a hydrocarbon resin.

Embodiment 13

The composition of any of embodiments 1-12, further comprising 0.05 to 1weight percent of a trihydrocarbyl phosphite.

Embodiment 14

The composition of any of embodiments 1-13, further comprising 0.5 to 5weight percent of linear low density polyethylene.

Embodiment 15

The composition of any of embodiments 1-14, comprising less than orequal to 1 weight percent of each of polyamides and polyesters.

Embodiment 16

A composition, comprising: 0.5 to 5 weight percent of a poly(phenyleneether)-polysiloxane block copolymer reaction product comprising a firstpoly(phenylene ether) and a poly(phenylene ether)-polysiloxane blockcopolymer; wherein the poly(phenylene ether)-polysiloxane blockcopolymer comprises a poly(phenylene ether) block comprising phenyleneether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; 50 to 70 weight percent of a secondpoly(phenylene ether) comprising a homopolymer of 2,6-dimethylphenol; 6to 14 weight percent of a flame retardant comprising an organophosphateester; 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; and15 to 25 weight percent of glass fibers; wherein the compositioncomprises less than or equal to 1 weight percent of each of polyamidesand polyesters; and wherein all weight percents are based on the totalweight of the composition.

Embodiment 16a

The composition of embodiment 1, wherein the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; wherein the composition comprises 0.5 to 5 weightpercent of the poly(phenylene ether)-polysiloxane block copolymerreaction product; wherein the composition further comprises 50 to 70weight percent of a second poly(phenylene ether) comprising ahomopolymer of 2,6-dimethylphenol; wherein the flame retardant comprisesthe organophosphate ester; wherein the composition comprises 6 to 14weight percent of the flame retardant; wherein the reinforcing fillercomprises glass fibers; wherein the composition comprises 15 to 25weight percent of the reinforcing filler; wherein the compositionfurther comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andwherein the composition comprises less than or equal to 1 weight percentof each of polyamides and polyesters.

Embodiment 17

The composition of claim 1, wherein the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; wherein the composition comprises 53 to 63 weightpercent of the poly(phenylene ether)-polysiloxane block copolymerreaction product; wherein the flame retardant comprises theorganophosphate ester; wherein the composition comprises 15 to 25 weightpercent of the flame retardant; wherein the reinforcing filler comprisesglass fibers; wherein the composition comprises 15 to 25 weight percentof the reinforcing filler; wherein the composition comprises less thanor equal to 1 weight percent of each of polyamides and polyesters, andless than or equal to 3 weight percent of polyolefins.

Embodiment 18

An article comprising a composition, comprising: 0.5 to 91 weightpercent of a poly(phenylene ether)-polysiloxane block copolymer reactionproduct comprising a first poly(phenylene ether) and a poly(phenyleneether)-polysiloxane block copolymer; 4 to 25 weight percent of a flameretardant comprising an organophosphate ester, a phosphazene, or acombination thereof; and 5 to 40 weight percent of a reinforcing filler;wherein all weight percents are based on the total weight of thecomposition.

Embodiment 19

The article of embodiment 18, wherein the article is a fuser holder foran electrophotographic copier.

Embodiment 20

The article of embodiment 18 or 19, wherein the composition furthercomprises 5 to 90.5 weight percent of a second poly(phenylene ether).

Embodiment 21

The article of embodiment 18, wherein the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; wherein the composition comprises 0.5 to 5 weightpercent of the poly(phenylene ether)-polysiloxane block copolymerreaction product; wherein the composition further comprises 50 to 70weight percent of a second poly(phenylene ether) comprising ahomopolymer of 2,6-dimethylphenol; wherein the flame retardant comprisesan organophosphate ester; wherein the composition comprises 6 to 14weight percent of the flame retardant; wherein the reinforcing fillercomprises glass fibers; wherein the composition comprises 15 to 25weight percent of the reinforcing filler; wherein the compositionfurther comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andwherein the composition comprises less than or equal to 1 weight percentof each of polyamides and polyesters.

Embodiment 22

The article of claim 18, wherein the poly(phenylene ether)-polysiloxaneblock copolymer comprises a poly(phenylene ether) block comprisingphenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; wherein the composition comprises 53 to 63 weightpercent of the poly(phenylene ether)-polysiloxane block copolymerreaction product; wherein the flame retardant comprises theorganophosphate ester; wherein the composition comprises 15 to 25 weightpercent of the flame retardant; wherein the reinforcing filler comprisesglass fibers; wherein the composition comprises 15 to 25 weight percentof the reinforcing filler; wherein the composition comprises less thanor equal to 1 weight percent of each of polyamides and polyesters, andless than or equal to 3 weight percent of polyolefins.

All ranges disclosed herein are inclusive of the endpoints, and theendpoints are independently combinable with each other. Each rangedisclosed herein constitutes a disclosure of any point or sub-rangelying within the disclosed range.

The invention is further illustrated by the following non-limitingexamples.

Comparative Examples 1-15

These comparative examples utilize poly(phenylene ether) homopolymer,rather than poly(phenylene ether)-polysiloxane block copolymer reactionproduct. Components used to prepare the compositions are summarized inTable 1.

TABLE 1 Component Description PPE 0.46 Poly(2,6-dimethyl-1,4-phenyleneether), CAS Reg. No. 25134-01-4, having an intrinsic viscosity of about0.46 deciliter per gram measured in chloroform at 25° C.; available asPPO ™ 646 from SABIC Innovative Plastics. PPE 0.40Poly(2,6-dimethyl-1,4-phenylene ether), CAS Reg. No. 25134-01-4, havingan intrinsic viscosity of about 0.40 deciliter per gram measured inchloroform at 25° C.; available as PPO ™ 640 from SABIC InnovativePlastics. PPE 0.33 Poly(2,6-dimethyl-1,4-phenylene ether), CAS Reg. No.25134-01-4, having an intrinsic viscosity of about 0.33 deciliter pergram measured in chloroform at 25° C.; available as PPO ™ 630 from SABICInnovative Plastics. PPE 0.30 Poly(2,6-dimethyl-1,4-phenylene ether),CAS Reg. No. 25134-01-4, having an intrinsic viscosity of about 0.30deciliter per gram measured in chloroform at 25° C.; available as PPO ™808 from SABIC Innovative Plastics. PPE-Si A mixture ofpoly(2,6-dimethyl-1,4-phenylene ether) (CAS Reg. No. 24938-67-8) andpoly(2,6-dimethyl-1,4-phenylene ether)-polydimethylsiloxane blockcopolymer (CAS Reg. No. 1202019-56-4), the mixture having a polysiloxanecontent of about 5 weight percent and an intrinsic viscosity of about0.4 deciliter per gram as measured in chloroform at 25° C.; preparedaccording to the procedure of U.S. Pat. No. 8,017,697 to Carrillo etal., Example 16. SEBS Polystyrene-poly(ethylene/butylene)-polystyrenetriblock copolymer, CAS Reg. No. 66070-58-4, having a polystyrenecontent of 30-33 weight percent and a weight average molecular weight of240,000-301,000 atomic mass units; obtained as KRATON ™ G1651 fromKraton Performance Polymers Inc. AO 168 Tris(2,4-di-tert-butylphenyl)phosphite, CAS Reg. No. 31570-04-4, available from BASF Corp. asIRGAFOS ™ 168, or from Chemtura as ALKANOX ™ 240. AO 626Bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, CAS Reg. No.26741-53-7, available from Chemtura as ULTRANOX ™ 626 HCR Saturatedpolyalicyclic hydrocarbon resin, CAS Reg. No. 64742-1, available fromArakawa Chemical as ARKON ™ P-125. HIPS Rubber-modified polystyrene, CASReg. No. 9003-55-8, available from SABIC Innovative Plastics asHIPS3190. Clay Water-washed kaolin clay, CAS Reg. No. 1332-58-7,available as KaMin POLYFIL ™ HG90 from KaMin Performance Minerals. MicaPhlogopite mica, CAS Reg. No. 12001-26-2, available from ImerysPerformance Minerals as SUZORITE ™ HK-200. Glass Fiber Chopped glassfiber having a diameter of about 14 micrometers and a pre-compoundedlength of about 4 millimeters; available from Owens Corning as 122Y-14C.Carbon Carbon black pigment, CAS Reg. No. 1333-86-4, available Blackfrom Cabot as BLACK PEARLS ™ 800 or MONARCH ™ 800. LLDPE Linear lowdensity polyethylene (copolymer of ethylene and 1-butene), CAS Reg. No.25087-34-7, having a density of 0.925 grams per cubic centimeter and amelt volume flow rate of 20 cubic centimeters per 10 minutes at 190° C.and 2.16 kilogram load, available from ExxonMobil as ESCORENE ™LL5100.09. MgO Magnesium oxide, CAS Reg. No. 1309-48-4, available fromKyowa Chemical Co. Ltd. as KYOWAMAG ™ 150. ZnS Zinc sulfide, CAS Reg.No. 1314-98-3, available from Sachtleben Chemie GmbH as SACHTOLITH ™TMHD-S. But-TPP t-Butylated triphenyl phosphate, CAS Reg. No. 220352-35 ,available as PHOSFLEX ™ 71B from Supresta LLC. BPADP Bisphenol Abis(diphenyl phosphate), CAS Reg. No. 181028-79-5; obtained asFYROFLEX ™ BDP from Supresta LLC, or REOFOS ™ BAPP from Great LakesChemical Co. Ltd.

Resin compositions were compounded on a 30 millimeter Werner &Pfleiderer ZSK twin-screw extruder operating at 350 rotations per minuteand a throughput of 18 kilograms per hour (40 pounds per hour) and usingbarrel set temperatures of 240° C./260° C./290° C./290° C./290° C. fromthe feed port to die. Glass fibers were added downstream to theextruder, while all other solid components were added at the feed throatand the liquid flame retardant (But-TPP or BPADP) was injected at a portbetween the feed throat and the glass fiber feed location. Thecompounded resins were pelletized by strand-cutting.

Test articles for ASTM determinations of heat deflection temperature andflexural properties were injection molded on a 120 Ton VanDorn injectionmolding machine using a barrel temperature of 288-310° C. (550-590° F.)and a mold temperature of about 88° C. (about 190° F.). Flame bars with1.0 or 1.5 millimeter thickness were injection molded on an 80 TonVanDorn injection molding machine using a barrel temperature of 299-321°C. (570-610° F.) and a mold temperature of 88-99° C. (190-210° F.).

Flame retardancy of injection molded flame bars was determined accordingto Underwriter's Laboratory Bulletin 94 “Tests for Flammability ofPlastic Materials, UL 94”, mm Vertical Burning Flame Test. Beforetesting, flame bars with a thickness of 1.0 or 1.5 millimeters wereconditioned at 23° C. and 50% relative humidity for at least 24 hours.In the UL 94 20 mm Vertical Burning Flame Test, a set of ten flame barswas tested. For each bar, a flame was applied to the bar then removed,and the time required for the bar to self-extinguish (first afterflametime, t1) was noted. The flame was then reapplied and removed, and thetime required for the bar to self-extinguish (second afterflame time,t2) and the post-flame glowing time (afterglow time, t3) were noted. Toachieve a rating of V-0, the afterflame times t1 and t2 for eachindividual specimen must have been less than or equal to 10 seconds; andthe total afterflame time for all ten specimens (t1 plus t2 for all tenspecimens) must have been less than or equal to 100 seconds; and thesecond afterflame time plus the afterglow time for each individualspecimen (t2+t3) must have been less than or equal to 30 seconds; and nospecimen can have flamed or glowed up to the holding clamp; and thecotton indicator cannot have been ignited by flaming particles or drops.To achieve a rating of V-1, the afterflame times t1 and t2 for eachindividual specimen must have been less than or equal to 30 seconds; andthe total afterflame time for all ten specimens (t1 plus t2 for all tenspecimens) must have been less than or equal to 500 seconds; and thesecond afterflame time plus the afterglow time for each individualspecimen (t2+t3) must have been less than or equal to 60 seconds; and nospecimen can have flamed or glowed up to the holding clamp; and thecotton indicator cannot have been ignited by flaming particles or drops.To achieve a rating of V-2, the afterflame times t1 and t2 for eachindividual specimen must have been less than or equal to 30 seconds; andthe total afterflame time for all ten specimens (t1 plus t2 for all tenspecimens) must have been less than or equal to 250 seconds; and thesecond afterflame time plus the afterglow time for each individualspecimen (t2+t3) must have been less than or equal to 60 seconds; and nospecimen can have flamed or glowed up to the holding clamp; but thecotton indicator can have been ignited by flaming particles or drops.Compositions not achieving a rating of V-2 were considered to havefailed.

Heat deflection temperature (HDT) values, expressed in units of degreescentigrade, were determined according to ASTM D 648-07 using 6.4millimeter thick bars (except where specified as 3.2 millimeterthickness), an edgewise test direction, a support span of 100millimeters (Method B), a stress of 1.82 megapascals, a deflection of0.25 millimeters at reading, a heating rate of 2° C./minute, and threespecimens per composition. Flexural modulus and flexural stress at breakvalues, each in units of megapascals, were determined at 23° C.according to ASTM D 790-07e1 using 6.4 millimeter thick bars, a supportspan of 101.6 millimeters, a test speed of 2.54 millimeters/minute (0.1inch/minute; Procedure A), and three specimens per composition.

Compositions and results are summarized in Table 2, where componentamounts are expressed in weight percent based on the total weight of thecomposition.

The Table 2 results show that the achievement of a flame retardancyrating of V-0 at a bar thickness of 1.5 millimeters is limited toComparative Examples 1-3 with very high flame retardant concentrations(≧21.00 weight percent) and correspondingly low heat deflectiontemperatures (≦112° C.). A flame retardancy rating of V-0 at 1.0millimeter thickness was only observed for Comparative Example 1 with alow heat deflection temperature of 106° C.

TABLE 2 C. Ex. 1 C. Ex. 2 C. Ex. 3 C. Ex. 4 COMPOSITIONS PPE 0.40 63 5649 67.5 BPADP 27 24 21 22.5 Glass fiber 10 20 30 10 PROPERTIES UL 94rating at 1.5 mm V-0 V-0 V-0 Fail UL 94 rating at 1.0 mm V-0 V-1 V-1 V-1HDT (° C.) 106 111 112 120 Flex. modulus (MPa) 4670 7120 9610 4670 Flex.stress at break (MPa) 144 153 159 145 C. Ex. 5 C. Ex. 6 C. Ex. 7 C. Ex.8 COMPOSITIONS PPE 0.40 60 52.5 72 64 BPADP 20 17.5 18 16 Glass fiber 2030 10 20 PROPERTIES UL 94 rating at 1.5 mm Fail V-1 V-1 V-1 UL 94 ratingat 1.0 mm V-1 V-1 V-1 V-1 HDT (° C.) 124 124 133 137 Flex. modulus (MPa)6850 9090 4370 6490 Flex. stress at break (MPa) 149 158 147 149 C. Ex. 9C. Ex. 10 C. Ex. 11 C. Ex. 12 COMPOSITIONS PPE 0.40 56 76.5 68 59.5BPADP 14 13.5 12 10.5 Glass fiber 30 10 20 30 PROPERTIES UL 94 rating at1.5 mm V-1 V-1 Fail V-1 UL 94 rating at 1.0 mm V-1 V-1 V-1 Fail HDT (°C.) 138 149 152 154 Flex. modulus (MPa) 8380 4250 6000 8050 Flex. stressat break (MPa) 151 145 142 152 C. Ex. 13 C. Ex. 14 C. Ex. 15COMPOSITIONS PPE 0.40 81 72 63 BPADP 9 8 7 Glass fiber 10 20 30PROPERTIES UL 94 rating at 1.5 mm V-1 V-1 V-1 UL 94 rating at 1.0 mm V-1V-1 V-1 HDT (° C.) 164 168 170 Flex. modulus (MPa) 4100 5830 7890 Flex.stress at break (MPa) 142 145 155

Comparative Examples 16-23

Eight comparative examples were prepared using poly(phenylene ether)homopolymer and the hydrogenated block copolymer SEBS. These examplesillustrate that it is not feasible to achieve a V-0 rating at 1.5millimeter thickness in a composition with a heat deflection temperatureof at least 150° C. and at least 10% glass fiber reinforcement, eventhough the corresponding unfilled compositions (Comparative Examples 16and 20) have a V-0 flame retardancy. Relative to the property balanceexhibited by the inventive composition, unfilled Comparative Examples 16and 20 are deficient in flexural modulus, and filled ComparativeExamples 17-19 and 21-23 are deficient in UL 94 rating, at least.

TABLE 3 C. Ex. 16 C. Ex. 17 C. Ex. 18 C. Ex. 19 COMPOSITIONS PPE 0.4684.70 76.23 67.76 72.00 BPADP 10.00 9.00 8.00 8.50 SEBS 5.00 4.5 4.004.25 AO 168 0.30 0.27 0.24 0.25 Glass fiber 0.00 10 20 10.00 Clay 0.000.00 0.00 5.00 PROPERTIES UL 94 rating at 1.5 mm V-0 V-1 V-1 V-1 HDT (°C.) 146 159 163 159 Flex. modulus (MPa) 2520 3721 5234 4235 Flex. stressat break (MPa) 106 122 132 136 C. Ex. 20 C. Ex. 21 C. Ex. 22 C. Ex. 23COMPOSITIONS PPE 0.46 82.70 74.43 66.16 70.30 BPADP 12.00 10.80 9.6010.20 SEBS 5.00 4.50 4.00 4.25 AO 168 0.30 0.27 0.24 0.25 Glass fiber0.00 10.00 20.00 10.00 Clay 0.00 0.00 0.00 5.00 PROPERTIES UL 94 ratingat 1.5 mm V-0 V-1 V-1 V-1 HDT (° C.) 139 152 156 153 Flex. modulus (MPa)2570 3937 5363 4297 Flex. stress at break (MPa) 108 128 131 135

Examples 1-6, Comparative Examples 24 and 25

These inventive and comparative examples illustrate the use of apoly(phenylene ether)-polysiloxane block copolymer in combination withthe hydrogenated block copolymer SEBS. Inventive Examples 1-6 all haveheat deflection temperature values of at least 155° C., as well as UL 94ratings of V-0 at 1.5 millimeter thickness, and flexural modulus valuesgreater than 3,500 megapascals. Comparative Examples 24 and 25 areunfilled and exhibit substantially lower heat deflection temperaturevalues, flexural modulus values, and flexural strength values.

TABLE 4 C. Ex. 24 Ex. 1 Ex. 2 Ex. 3 COMPOSITIONS PPE-Si 87.70 78.9370.16 74.55 BPADP 7.00 6.30 5.60 5.95 SEBS 5.00 4.50 4.00 4.25 AO 1680.30 0.27 0.24 0.25 Glass fiber 0.00 10.00 20.00 10.00 Clay 0.00 0.000.00 5.00 PROPERTIES UL 94 rating at 1.5 mm V-0 V-0 V-0 V-0 HDT (° C.)149 163 168 163 Flex. modulus (MPa) 2310 3506 4942 3891 Flex. stress atbreak (MPa) 94 119 133 125 C. Ex. 25 Ex. 4 Ex. 5 Ex. 6 COMPOSITIONSPPE-Si 85.70 77.13 68.56 72.85 BPADP 9.00 8.10 7.20 7.65 SEBS 5.00 4.504.00 4.25 AO 168 0.30 0.27 0.24 0.25 Glass fiber 0.00 10.00 20.00 10.00Clay 0.00 0.00 0.00 5.00 PROPERTIES UL 94 rating at 1.5 mm V-0 V-0 V-0V-0 HDT (° C.) 140 155 160 158 Flex. modulus (MPa) 2350 3739 5027 4039Flex. stress at break (MPa) 96 123 130 129

Examples 7-15, Comparative Example 26

These inventive and comparative examples illustrate means of achievingimproved melt flow.

Melt volume flow rate (MVR) values, expressed in units of cubiccentimeters per 10 minutes, were determined according to ASTM D 1238-04at 300° C. using a load of 5 kilograms, automatic timing (Procedure B),a capillary diameter of 2.0955 millimeters, a capillary length of 8.00millimeters, a test specimen form of pellets, specimen conditioning forone hour at 70° C. prior to testing, and one sample with five readingsper composition.

The results in Table 5 show that the inventive compositions can bemodified to increase melt flow while still maintaining a high heatdeflection temperature and a UL 94 rating of V-0 at 1.5 millimeters.Inventive Example 13 shows that a reduced concentration ofpoly(phenylene ether)-polysiloxane block copolymer also still results inV-0 at 1.5 mm. Inventive Example 15 illustrates the use of a mixedfiller reinforcement. The examples also show that melt flow increasescan be accomplished through use of a hydrocarbon resin flow promoter(Examples 10-15) and/or a phosphite antioxidant like AO 626. InventiveExample 7, without either hydrocarbon resin or phosphite antioxidant,exhibits relatively lower melt flow. Comparative Example 26 shows againthat with poly(phenylene ether) homopolymer rather than poly(phenyleneether)-polysiloxane block copolymer reaction product, even a higherconcentration of flame retardant does not result in V-0 flammabilityrating at 1.5 millimeters.

TABLE 5 Ex. 7 Ex. 8 Ex. 9 Ex. 10 Ex. 11 COMPOSITIONS PPE-Si 68.66 68.2667.86 68.26 68.26 PPE 0.40 0.00 0.00 0.00 0.00 0.00 BPADP 6.97 6.97 6.976.97 6.97 SEBS 3.98 3.98 3.98 1.99 0.00 HCR 0.00 0.00 0.00 1.99 3.98 AO626 0.00 0.40 0.80 0.40 0.40 Carbon black 0.50 0.50 0.50 0.50 0.50 Glassfiber 19.90 19.90 19.90 19.90 19.90 Mica 0.00 0.00 0.00 0.00 0.00PROPERTIES UL 94 rating at 1.5 mm V-0 V-0 V-0 V-0 V-0 HDT (° C.) 161 158157 156 153 MVR (cc/10min) 2.8 8.8 12.6 11.6 14.1 Flex. modulus (MPa)5150 5180 5310 5320 5500 Flex. stress at break (MPa) 137 136 131 131 138Ex. 12 Ex. 13 Ex. 14 Ex. 15 C. Ex. 26 COMPOSITIONS PPE-Si 67.86 33.4377.21 72.74 0.00 PPE 0.40 0.00 33.43 0.00 0.00 65.27 BPADP 6.97 8.367.96 7.46 9.95 SEBS 0.00 1.99 1.99 1.99 3.98 HCR 3.98 1.99 1.99 1.990.00 AO 626 0.80 0.40 0.40 0.40 0.40 Carbon black 0.50 0.50 0.50 0.500.50 Glass fiber 19.90 19.90 9.95 9.95 19.90 Mica 0.00 0.00 0.00 4.980.00 PROPERTIES UL 94 rating at 1.5 mm V-0 V-0 V-0 V-0 V-1 HDT (° C.)151 153 152 153 155 MVR (cc/10min) 21.8 13.1 16.3 13.4 8.28 Flex.modulus (MPa) 5660 5480 3910 4367 5640 Flex. stress at break (MPa) 134133 122 124 136

Examples 16-19

These inventive examples illustrate that omission of hydrogenated blockcopolymer is associated with even higher heat deflection temperaturevalues.

TABLE 6 Ex. 16 Ex. 17 Ex. 18 Ex. 19 COMPOSITIONS PPE-Si 76.32 71.8467.86 73.83 BPADP 7.46 6.97 6.97 4.98 HCR 0.00 0.00 3.98 0.00 AO 6260.80 0.80 0.80 0.80 Carbon black 0.50 0.50 0.50 0.50 Glass fiber 9.9519.90 19.90 19.90 Mica 4.98 0.00 0.00 0.00 PROPERTIES UL 94 rating at1.5 mm V-0 V-0 V-0 V-0 HDT (° C.) 157 159 153 168 MVR (cc/10min) 18 1423 9 Flex. modulus (MPa) 4700 5680 5650 5520 Flex. stress at break (MPa)118 136 128 135

Examples 20 and 21, Comparative Examples 27 and 28

These inventive and comparative examples, all with 20% glass fiberreinforcement, illustrate that the improved flame retardancy associatedwith the use of poly(phenylene ether)-polysiloxane block copolymerreaction product rather than poly(phenylene ether) homopolymer can beobtained without sacrificing heat resistance. Comparative Example 28also illustrates that a reduction of HIPS concentration and increases inflame retardant and poly(phenylene ether) homopolymer, all relative toComparative Example 27, are not sufficient to result in V-0 flameperformance at 1.5 millimeters.

TABLE 7 C. Ex. 27 Ex. 20 C. Ex. 28 Ex. 21 COMPOSITIONS PPE 0.46 48.000.00 55.00 0.00 PPE-Si 0.00 52.00 0.00 59.00 HIPS 24.50 20.50 16.5012.50 But-TPP 6.00 6.00 7.00 7.00 LLDPE 1.00 1.00 1.00 1.00 AO 626 0.300.30 0.30 0.30 ZnS 0.10 0.10 0.10 0.10 MgO 0.10 0.10 0.10 0.10 Glassfiber 20.00 20.00 20.00 20.00 PROPERTIES UL 94 rating at 1.5 mm V-1 V-0V-1 V-0 HDT at 3.2 mm (° C.) 132 132 135 137

Examples 22 and 23, Comparative Examples 29 and 30

These inventive and comparative examples, all with 30% glass fiberreinforcement, further illustrate that the improved flame retardancyassociated with the use of poly(phenylene ether)-polysiloxane blockcopolymer reaction product rather than poly(phenylene ether) homopolymercan be obtained without substantially sacrificing heat resistance.Comparative Example 30 also illustrates that a reduction of HIPSconcentration and increases in flame retardant and poly(phenylene ether)homopolymer, all relative to Comparative Example 29, are not sufficientto result in V-0 flame performance at 1.5 millimeters.

TABLE 8 C. Ex. 29 Ex. 22 C. Ex. 30 Ex. 23 COMPOSITIONS PPE 0.46 49.000.00 51.50 0.00 PPE-Si 0.00 53.00 0.00 56.00 HIPS 12.00 8.00 8.50 4.00But-TPP 7.50 7.50 8.50 8.50 LLDPE 1.00 1.00 1.00 1.00 AO 168 0.30 0.300.30 0.30 ZnS 0.10 0.10 0.10 0.10 MgO 0.10 0.10 0.10 0.10 Glass fiber30.00 30.00 30.00 30.00 PROPERTIES UL 94 rating at 1.5 mm V-1 V-0 V-1V-0 HDT at 3.2 mm (° C.) 136 135 135 136

Examples 24-26, Comparative Examples 31-36

These inventive and comparative examples demonstrate that it is alsopossible to achieve a UL 94 rating of V-0 at a thickness of 0.75millimeters in a 20% glass fiber reinforced composition containingpoly(phenylene ether)-polysiloxane block copolymer, while maintaining aheat deflection temperature greater than 110° C. Comparative Example 36achieved a V-0 rating but was deficient in heat deflection temperature.

TABLE 9 Ex. 24 Ex. 25 Ex. 26 C. Ex. 31 C. Ex. 32 C. Ex. 33 C. Ex. 34 C.Ex. 35 C. Ex. 36 COMPOSITIONS PPE-Si 57.81 59.80 61.79 0.00 0.00 0.000.00 0.00 0.00 PPE 0.40 0.00 0.00 0.00 57.81 54.83 51.84 0.00 0.00 0.00PPE 0.46 0.00 0.00 0.00 0.00 0.00 0.00 57.81 54.83 51.84 BPADP 19.9017.91 15.92 19.90 22.89 25.87 19.90 22.89 25.87 Glass fiber 19.90 19.9019.90 19.90 19.90 19.90 19.90 19.90 19.90 LLDPE 1.49 1.49 1.49 1.49 1.491.49 1.49 1.49 1.49 AO 168 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10ZnS 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 MgO 0.15 0.15 0.15 0.150.15 0.15 0.15 0.15 0.15 Carbon black 0.50 0.50 0.50 0.50 0.50 0.50 0.500.50 0.50 PROPERTIES UL 94 rating at 0.75 mm V-0 V-0 V-0 V-1 V-1 V-1 V-1V-1 V-0 HDT (° C.) 113 121 128 119 109 100 120 110 100 Flex. modulus(MPa) 6094 6178 6104 6530 6570 6661 6638 6539 6717 Flex. stress at break(MPa) 155 158 158 160 155 145 161 153 146

Examples 27-43, Comparative Examples 37-39

These examples illustrate the attainment of a UL 94 V-0 rating at athickness of 1.5 millimeters by compositions comprising as little as 0.5weight percent of a poly(phenylene ether)-polysiloxane block copolymerreaction product. They further illustrate compositions comprising afirst poly(phenylene ether) (derived from the poly(phenyleneether)-polysiloxane block copolymer reaction product) and a secondpoly(phenylene ether) (separately added; see Examples 28-43).

Notched Izod values and unnotched Izod values, each expressed in unitsof joules/meter, were determined according to ASTM D256-08 at 25° C.using a hammer energy of 2 foot-pounds (2.71 joules), and barcross-sectional dimensions of 3.2 by 12.7 millimeters. Flexural modulus,flexural stress at yield, and flexural stress at break values, each inunits of megapascals, were determined at 23° C. according to ASTM D790-07e1 using 6.4 millimeter thick bars, a support span of 101.6millimeters, a test speed of 2.54 millimeters/minute (0.1 inch/minute;Procedure A), and three specimens per composition. Tensile modulus andtensile stress at break values, each expressed in units of megapascals,and tensile elongation at break values, expressed in units of percent,were determined according to ASTM D 638-08 at 23° C. using a Type I barhaving a thickness of 3.2 millimeters, a gage length of 50 millimeters,and a testing speed of 5 millimeters per minute.

The results demonstrate that compositions with 0.5 to 40 weight percentpoly(phenylene ether)-polysiloxane block copolymer reaction productexhibit a UL 94 V-0 rating at a thickness of 1.5 millimeters. Althoughphysical properties were not measured for all samples, the availableresults show that compositions with 2 to 40 weight percentpoly(phenylene ether)-polysiloxane block copolymer reaction productfurther exhibit a heat deflection temperature of at least 150° C.determined according to ASTM D 648-07 using a stress of 1.82 megapascals(MPa) and a sample thickness of 6.4 millimeters, and a flexural modulusof at least 5,000 megapascals measured at 23° C. according to ASTM D790-07e1 using a sample thickness of 6.4 millimeters. ComparativeExamples 37 and 38, without poly(phenylene ether)-polysiloxane blockcopolymer, and Comparative Example 39, with only 0.4 weight percentpoly(phenylene ether)-polysiloxane block copolymer, do not achieve a UL94 V-0 rating at a thickness of 1.5 millimeters.

TABLE 10 Ex. 27 Ex. 28 Ex. 29 Ex. 30 COMPOSITIONS PPE-Si 68.2 40.0 30.020.0 PPE 0.33 0.0 0.0 0.0 0.0 PPE 0.30 0.0 30.8 39.3 48.8 PDMS/silica0.0 0.0 0.0 0.0 PDMS 0.0 0.0 0.0 0.0 HCR 4.0 0.0 0.0 0.0 SEBS 0.0 1.02.0 2.0 AO 626 0.8 0.0 0.0 0.0 AO 168 0.0 0.2 0.2 0.2 BPADP 7.0 8.0 8.59.0 Glass fiber 20.0 20.0 20.0 20.0 Polysiloxane content 3.4 2.0 1.5 1.0PROPERTIES UL Rating at 1.5 mm V-0 V-0 V-0 V-0 UL Rating at 1.0 mm V-0V-0 V-0 V-0 HDT (° C.) 153 159 159 157 Notched Izod (J/m) 69.8 87.8 95.290.8 Unnotched Izod (J/m) 338 466 478 492 Flex. modulus (MPa) 5460 52405210 5090 Flex. stress at yield (MPa) 131 140 143 140 Flex. stress atbreak (MPa) 132 141 140 140 Tens. modulus (MPa) 6900 6818 6784 6768Tensile stress at break (MPa) 114 119 118 120 Tens. elong. at break (%)2.2 2.5 2.5 2.5 Ex. 31 C. Ex. 37 Ex. 32 Ex. 33 COMPOSITIONS PPE-Si 10.00.0 20.0 10.0 PPE 0.33 0.0 0.0 0.0 0.0 PPE 0.30 56.8 65.8 47.8 57.8PDMS/silica 0.0 0.0 0.0 0.0 PDMS 0.0 0.0 0.0 0.0 HCR 0.0 0.0 0.0 0.0SEBS 3.0 4.0 2.0 2.0 AO 626 0.0 0.0 0.0 0.0 AO 168 0.2 0.2 0.20 0.20BPADP 10.0 10.0 10.0 10.0 Glass fiber 20.0 20.0 20.0 20.0 Polysiloxanecontent 0.5 0.0 1.0 0.5 PROPERTIES UL Rating at 1.5 mm V-0 V-1 V-0 V-0UL Rating at 1.0 mm V-0 V-1 — — HDT (° C.) 153 153 153 154 Notched Izod(J/m) 96 101 79.8 82.0 Unnotched Izod (J/m) 457 515 495 516 Flex.modulus (MPa) 5180 5270 5330 5390 Flex. stress at yield (MPa) 143 147 —— Flex. stress at break (MPa) 143 144 133 135 Tens. modulus (MPa) 67846694 — — Tensile stress at break (MPa) 120 117 — — Tens. elong. at break(%) 2.5 2.5 — — Ex. 34 Ex. 35 Ex. 36 Ex. 37 COMPOSITIONS PPE-Si 8.0 6.04.0 2.0 PPE 0.33 0.0 0.0 0.0 0.0 PPE 0.30 59.8 61.8 63.8 65.8PDMS/silica 0.0 0.0 0.0 0.0 PDMS 0.0 0.0 0.0 0.0 HCR 0.0 0.0 0.0 0.0SEBS 2.0 2.0 2.0 2.0 AO 626 0.0 0.0 0.0 0.0 AO 168 0.20 0.20 0.2 0.20BPADP 10.0 10.0 10.0 10.0 Glass fiber 20.0 20.0 20.0 20.0 Polysiloxanecontent 0.4 0.3 0.2 0.1 PROPERTIES UL Rating at 1.5 mm V-0 V-0 V-0 V-0UL Rating at 1.0 mm — — — — HDT (° C.) 155 155 155 155 Notched Izod(J/m) 86.6 83.3 81.1 79.5 Unnotched Izod (J/m) 503 511 496 475 Flex.modulus (MPa) 5400 5400 5460 5490 Flex. stress at yield (MPa) — — — —Flex. stress at break (MPa) 134 138 133 138 Tens. modulus (MPa) — — — —Tensile stress at break (MPa) — — — — Tens. elong. at break (%) — — — —C. Ex. 38 Ex. 38 Ex. 39 Ex. 40 COMPOSITIONS PPE-Si 0.0 4.0 2.0 1.0 PPE0.33 0.0 63.8 65.8 66.8 PPE 0.30 67.8 0.0 0.0 0.0 PDMS/silica 0.0 0.00.0 0.0 PDMS 0.0 0.0 0.0 0.0 HCR 0.0 0.0 0.0 0.0 SEBS 2.0 2.0 2.0 2.0 AO626 0.0 0.0 0.0 0.0 AO 168 0.20 0.20 0.20 0.2 BPADP 10.0 10.0 10.0 10.0Glass fiber 20.0 20.0 20.0 20.0 Polysiloxane content 0.0 0.2 0.1 0.05PROPERTIES UL Rating at 1.5 mm V-1 V-0 V-0 V-0 UL Rating at 1.0 mm — — —— HDT (° C.) 156 — — — Notched Izod (J/m) 81.3 — — — Unnotched Izod(J/m) 475 — — — Flex. modulus (MPa) 5560 — — — Flex. stress at yield(MPa) — — — — Flex. stress at break (MPa) 135 — — — Tens. modulus (MPa)— — — — Tensile stress at break (MPa) — — — — Tens. elong. at break (%)— — — — Ex. 41 Ex. 42 Ex. 43 C. Ex. 39 COMPOSITIONS PPE-Si 0.50 1.600.80 0.40 PPE 0.33 67.3 66.2 67.0 67.4 PPE 0.30 0.0 0.0 0.0 0.0PDMS/silica 0.0 0.0 0.0 0.0 PDMS 0.0 0.0 0.0 0.0 HCR 0.0 0.0 0.0 0.0SEBS 2.0 2.0 2.0 2.0 AO 626 0.0 0.0 0.0 0.0 AO 168 0.20 0.20 0.20 0.20BPADP 10.0 10.0 10.0 10.0 Glass fiber 20.0 20.0 20.0 20.0 Polysiloxanecontent 0.025 0.08 0.04 0.02 PROPERTIES UL Rating at 1.5 mm V-0 V-0 V-0V-1 UL Rating at 1.0 mm — — — — HDT (° C.) — — — — Notched Izod (J/m) —— — — Unnotched Izod (J/m) — — — — Flex. modulus (MPa) — — — — Flex.stress at yield (MPa) — — — — Flex. stress at break (MPa) — — — — Tens.modulus (MPa) — — — — Tensile stress at break (MPa) — — — — Tens. elong.at break (%) — — — —

The invention claimed is:
 1. A composition, comprising: 0.5 to 91 weightpercent of a poly(phenylene ether)-polysiloxane block copolymer reactionproduct comprising a first poly(phenylene ether) and a poly(phenyleneether)-polysiloxane block copolymer; 5 to 90.5 weight percent of asecond poly(phenylene ether); 4 to 25 weight percent of a flameretardant comprising an organophosphate ester, a phosphazene, or acombination thereof; and 5 to 40 weight percent of a reinforcing filler;wherein all weight percents are based on the total weight of thecomposition.
 2. The composition of claim 1, exhibiting a flammabilityrating of V-0 at a sample thickness less than or equal to 1.5millimeters in the 20 millimeter Vertical Burning Flame Test ofUnderwriter's Laboratory Bulletin 94 “Tests for Flammability of PlasticMaterials, UL 94”, a heat deflection temperature of at least 110° C.determined according to ASTM D 648-07 using a stress of 1.82 megapascals(MPa) and a sample thickness of 6.4 millimeters, and a flexural modulusof at least 3,500 megapascals measured at 23° C. according to ASTM D790-07e1 using a sample thickness of 6.4 millimeters.
 3. The compositionof claim 1, comprising 0.5 to 5 weight percent of the poly(phenyleneether)-polysiloxane block copolymer reaction product, and 30 to 90.5weight percent of the second poly(phenylene ether).
 4. The compositionof claim 1, wherein the poly(phenylene ether)-polysiloxane blockcopolymer comprises a poly(phenylene ether) block comprising phenyleneether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to
 60. 5. The composition of claim 1, wherein thepoly(phenylene ether)-polysiloxane block copolymer contributes 0.025 to5 weight percent of polysiloxane to the composition.
 6. The compositionof claim 1, wherein the flame retardant comprises an organophosphateester.
 7. The composition of claim 1, wherein the flame retardantcomprises a phosphazene.
 8. The composition of claim 1, wherein thereinforcing filler is selected from the group consisting of glassfibers, carbon fibers, wollastonite, halloysite, clays, talcs, micas,glass flakes, solid glass beads, hollow glass beads, solid ceramicbeads, hollow ceramic beads, and combinations thereof.
 9. Thecomposition of claim 1, wherein the reinforcing filler comprises glassfibers.
 10. The composition of claim 1, further comprising 2 to 10weight percent of an impact modifier selected from the group consistingof rubber-modified polystyrenes, unhydrogenated block copolymers of analkenyl aromatic monomer and a conjugated diene, hydrogenated blockcopolymers of an alkenyl aromatic monomer and a conjugated diene,acrylate core-shell impact modifiers, and combinations thereof.
 11. Thecomposition of claim 1, further comprising 1 to 8 weight percent of ahydrocarbon resin.
 12. The composition of claim 1, further comprising0.05 to 1 weight percent of a trihydrocarbyl phosphite.
 13. Thecomposition of claim 1, further comprising 0.5 to 5 weight percent oflinear low density polyethylene.
 14. The composition of claim 1,comprising less than or equal to 1 weight percent of each of polyamidesand polyesters.
 15. The composition of claim 1, wherein thepoly(phenylene ether)-polysiloxane block copolymer comprises apoly(phenylene ether) block comprising phenylene ether repeating unitshaving the structure

a polysiloxane block having the structure

wherein n is 30 to 60; wherein the composition comprises 0.5 to 5 weightpercent of the poly(phenylene ether)-polysiloxane block copolymerreaction product; wherein the composition comprises 50 to 70 weightpercent of the second poly(phenylene ether), wherein the secondpoly(phenylene ether) comprises a homopolymer of 2,6-dimethylphenol;wherein the flame retardant comprises the organophosphate ester; whereinthe composition comprises 6 to 14 weight percent of the flame retardant;wherein the reinforcing filler comprises glass fibers; wherein thecomposition comprises 15 to 25 weight percent of the reinforcing filler;wherein the composition further comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andwherein the composition comprises less than or equal to 1 weight percentof each of polyamides and polyesters.
 16. An article comprising acomposition, comprising: 0.5 to 91 weight percent of a poly(phenyleneether)-polysiloxane block copolymer reaction product comprising a firstpoly(phenylene ether) and a poly(phenylene ether)-polysiloxane blockcopolymer; 5 to 90.5 weight percent of a second poly(phenylene ether); 4to 25 weight percent of a flame retardant comprising an organophosphateester, a phosphazene, or a combination thereof; and 5 to 40 weightpercent of a reinforcing filler; wherein all weight percents are basedon the total weight of the composition.
 17. The article of claim 16,wherein the article is a fuser holder for an electrophotographic copier.18. The article of claim 16, wherein the poly(phenyleneether)-polysiloxane block copolymer comprises a poly(phenylene ether)block comprising phenylene ether repeating units having the structure

a polysiloxane block having the structure

wherein n is 30 to 60; wherein the composition comprises 0.5 to 5 weightpercent of the poly(phenylene ether)-polysiloxane block copolymerreaction product; wherein the composition comprises 50 to 70 weightpercent of the second poly(phenylene ether), wherein the secondpoly(phenylene ether) comprises a homopolymer of 2,6-dimethylphenol;wherein the flame retardant comprises an organophosphate ester; whereinthe composition comprises 6 to 14 weight percent of the flame retardant;wherein the reinforcing filler comprises glass fibers; wherein thecomposition comprises 15 to 25 weight percent of the reinforcing filler;wherein the composition further comprises 1 to 8 weight percent of apolystyrene-poly(ethylene-butylene)-polystyrene triblock copolymer; andwherein the composition comprises less than or equal to 1 weight percentof each of polyamides and polyesters.